Fatty acid taste quality information via GPR120 in the anterior tongue of mice.

Fatty acid taste quality information via GPR120 in the anterior tongue of mice.

Acta Physiol (Oxf). 2018 Oct 30;:e13215

Authors: Yasumatsu K, Iwata S, Inoue M, Ninomiya Y

Abstract
AIM: To elucidate whether fatty acid taste has a quality that does not overlap with other primary qualities, we investigated potential neuron types coding fatty acid information and how GPR120 is involved.
METHODS: Single fibre recordings in the chorda tympani (CT) nerve and behavioural response measurements using a conditioned taste aversion paradigm were performed in GPR120-knockout (KO) and wild-type (WT) mice.
RESULTS: Single fibres can be classified into fatty acid (F)-, S-, M-, electrolyte (E)-, Q-, and N-type groups according to the maximal response among oleic acid, sucrose, monopotassium glutamate (MPG), HCl, quinine hydrochloride, and NaCl, respectively. Among fibres, 4.0% in GPR120-KO and 17.9% in WT mice showed a maximal response to oleic acid (F-type). Furthermore, half or more of S- and M-type fibres showed responses to fatty acids in both mouse strains, although the thresholds in KO mice were significantly higher and impulse frequencies lower than those in WT mice. GPR120-KO mice conditioned to avoid linoleic acid showed generalized stimulus avoidances for MPG, indicating qualitative similarity between linoleic acid and MPG. The KO mice showed a higher generalization threshold for linoleic acid than that of WT mice.
CONCLUSION: Fatty acid taste is suggested to have a unique quality owing to the discovery of F-type fibres, with GPR120 involved in neural information pathways for a unique quality and palatable taste qualities in the mouse CT nerve. GPR120 plays roles in distinguishing fatty acid taste from other primary tastes and the detection of low linoleic acid concentrations. This article is protected by copyright. All rights reserved.

PMID: 30375738 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2RoM8P6

Machine learning in human olfactory research.

Related Articles

Machine learning in human olfactory research.

Chem Senses. 2018 Oct 27;:

Authors: Lötsch J, Kringel D, Hummel T

Abstract
The complexity of the human sense of smell is increasingly reflected in complex and high-dimensional data, which opens opportunities for data driven approaches that complement hypothesis driven research. Contemporary developments in computational and data science, with its currently most popular implementation as machine learning, facilitate complex data driven research approaches. The use of machine-learning in human olfactory research included major approaches comprising (i) the study of the physiology of pattern-based odor detection and recognition processes, (ii) pattern recognition in olfactory phenotypes, (iii) the development of complex disease biomarkers including olfactory features, (iv) odor prediction from physicochemical properties of volatile molecules and (v) knowledge discovery in publicly available big databases. A limited set of unsupervised and supervised machine-learned methods has been used in these projects, however, the increasing use of contemporary methods of computational science is reflected in a growing number of reports employing machine learning for human olfactory research. This review provides key concepts of machine learning and summarizes current applications on human olfactory data.

PMID: 30371751 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2qizkOx

Spilanthol enhances sensitivity to sodium in mouse taste bud cells.

Spilanthol enhances sensitivity to sodium in mouse taste bud cells.

Chem Senses. 2018 Oct 26;:

Authors: Xu J, Lewandowski B, Miyazawa T, Shoji Y, Yee K, Bryant B

Abstract
Overconsumption of NaCl has been linked to increased hypertension related morbidity. Compounds that can enhance NaCl responses in taste cells could help reduce human NaCl consumption without sacrificing perceived saltiness. Spilanthol is an unsaturated alkylamide isolated from the Jambu plant (Acmella oleracea) that can induce tingling, pungency, and numbing in the mouth. Structurally similar fatty acid amides, such as sanshool, elicit numbing and tingling sensations by inhibiting 2-pore domain potassium leak channels on trigeminal sensory neurons. Even when insufficient to induce action potential firing, leak current inhibition causes depolarization and increased membrane resistance which combine to make cells more sensitive to subsequent depolarizing stimuli, such as NaCl. Using calcium imaging, we tested whether spilanthol alters sensitivity to NaCl in isolated circumvallate taste bud cells and trigeminal sensory neurons of mice (Mus musculus). Micromolar spilanthol elicited little to no response in taste bud cells or trigeminal neurons. These same perithreshold concentrations of spilanthol significantly enhanced responses to NaCl (140 and 200 mM) in taste bud cells. Trigeminal neurons, however, exhibited response enhancement only at the highest concentrations of NaCl and spilanthol tested. Using a combination of potassium depolarization, immunohistochemistry and Trpm5-GFP and Tas1r3-GFP mice to characterize taste bud cells by type, we found spilanthol enhancement of NaCl responses most prevalent in NaCl-responsive type III cells, and commonly observed in NaCl-responsive type II cells. Our results indicate that spilanthol enhances NaCl responses in taste bud cells and point to a family of compounds that may have utility as salty taste enhancers.

PMID: 30364996 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2SnvXmj

Role of Taste Receptors as Sentinels of Innate Immunity in the Upper Airway.

Role of Taste Receptors as Sentinels of Innate Immunity in the Upper Airway.

J Pathog. 2018;2018:9541987

Authors: Patel NN, Workman AD, Cohen NA

Abstract
Evidence is emerging that shows taste receptors serve functions outside of taste sensation of the tongue. Taste receptors have been found in tissue across the human body, including the gastrointestinal tract, bladder, brain, and airway. These extraoral taste receptors appear to be important in modulating the innate immune response through detection of pathogens. This review discusses taste receptor signaling, focusing on the G-protein-coupled receptors that detect bitter and sweet compounds in the upper airway epithelium. Emphasis is given to recent studies which link the physiology of sinonasal taste receptors to clinical manifestation of upper airway disease.

PMID: 30363975 [PubMed]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2zb81Ki

Tissue-dependent expression of bitter receptor TAS2R38 mRNA.

Related Articles

Tissue-dependent expression of bitter receptor TAS2R38 mRNA.

Chem Senses. 2018 Oct 23;:

Authors: Douglas JE, Lin C, Mansfield CJ, Arayata CJ, Cowart BJ, Spielman AI, Adappa ND, Palmer JN, Cohen NA, Reed DR

Abstract
TAS2R38 is a human bitter receptor gene with a common but inactive allele; people homozygous for the inactive form cannot perceive low concentrations of certain bitter compounds. The frequency of the inactive and active form of this receptor is nearly equal in many human populations, and heterozygotes with one copy of the active form and one copy of the inactive form have the most common diplotype. However, even though they have the same genotype, heterozygotes differ markedly in their perception of bitterness, perhaps in part because of differences in TAS2R38 mRNA expression. Other tissues express this receptor too, including the nasal sinuses, where it contributes to pathogen defense. We therefore wondered whether heterozygous people had a similar wide range of TAS2R38 mRNA in sinonasal tissue and whether those with higher TAS2R38 mRNA expression in taste tissue were similarly high-expressers in nasal tissue. To that end, we measured gene expression by qPCR in taste and sinonasal tissue and found that expression abundance in one tissue was not related to the other. We confirmed the independence of expression in other tissues pairs expressing TAS2R38 mRNA, such as pancreas and small intestine, using autopsy data from the Genotype-Tissue Expression (GTEx) project (although people with high expression of TAS2R38 mRNA in colon also tended to have higher expression in the small intestine). Thus, taste tissue TAS2R38 mRNA expression among heterozygotes is unlikely to predict expression in other tissues, perhaps reflecting tissue-dependent function, and hence regulation, of this protein.

PMID: 30351347 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2EGD1HP

Respiration modulates olfactory memory consolidation in humans.

Related Articles

Respiration modulates olfactory memory consolidation in humans.

J Neurosci. 2018 Oct 22;:

Authors: Arshamian A, Iravani B, Majid A, Lundström JN

Abstract
In mammals, respiratory-locked hippocampal rhythms are implicated in the scaffolding and transfer of information between sensory and memory networks. These oscillations are entrained by nasal respiration and driven by the olfactory bulb. They then travel to the piriform cortex where they propagate further downstream to the hippocampus and modulate neural processes critical for memory formation. In humans, bypassing nasal airflow through mouth-breathing abolishes these rhythms and impacts encoding as well as recognition processes thereby reducing memory performance. It has been hypothesized that similar behavior should be observed for the consolidation process, the stage between encoding and recognition, were memory is reactivated and strengthened. However, direct evidence for such an effect is lacking in human and non-human animals. Here we tested this hypothesis by examining the effect of respiration on consolidation of episodic odor memory. In two separate sessions, female and male participants encoded odors followed by a one hour awake resting consolidation phase where they either breathed solely through their nose or mouth. Immediately after the consolidation phase, memory for odors was tested. Recognition memory significantly increased during nasal respiration compared to mouth respiration during consolidation. These results provide the first evidence that respiration directly impacts consolidation of episodic events, and lends further support to the notion that core cognitive functions are modulated by the respiratory cycle.SIGNIFICANCE STATEMENTMemories pass through three main stages in their development: encoding, consolidation, and retrieval. Growing evidence from animal and human studies suggests that respiration plays an important role in the behavioral and neural mechanisms associated with encoding and recognition. Specifically nasal, but not mouth, respiration entrains neural oscillations that enhance the encoding and recognition processes. We demonstrate that respiration also affects the consolidation stage. Breathing through the nose compared to the mouth during consolidation enhances recognition memory. This demonstrates, first, that nasal respiration is important during the critical period were memories are reactivated and strengthened. Second, it suggests that the neural mechanisms responsible may emerge from nasal respiration.

PMID: 30348674 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2PftGuR

Bioinspired Electronics for Artificial Sensory Systems.

Related Articles

Bioinspired Electronics for Artificial Sensory Systems.

Adv Mater. 2018 Oct 21;:e1803637

Authors: Jung YH, Park B, Kim JU, Kim TI

Abstract
Humans have a myriad of sensory receptors in different sense organs that form the five traditionally recognized senses of sight, hearing, smell, taste, and touch. These receptors detect diverse stimuli originating from the world and turn them into brain-interpretable electrical impulses for sensory cognitive processing, enabling us to communicate and socialize. Developments in biologically inspired electronics have led to the demonstration of a wide range of electronic sensors in all five traditional categories, with the potential to impact a broad spectrum of applications. Here, recent advances in bioinspired electronics that can function as potential artificial sensory systems, including prosthesis and humanoid robots are reviewed. The mechanisms and demonstrations in mimicking biological sensory systems are individually discussed and the remaining future challenges that must be solved for their versatile use are analyzed. Recent progress in bioinspired electronic sensors shows that the five traditional senses are successfully mimicked using novel electronic components and the performance regarding sensitivity, selectivity, and accuracy have improved to levels that outperform human sensory organs. Finally, neural interfacing techniques for connecting artificial sensors to the brain are discussed.

PMID: 30345558 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2AnrybU

Biomarkers in Chronic Rhinosinusitis with Nasal Polyps.

Biomarkers in Chronic Rhinosinusitis with Nasal Polyps.

Immunol Allergy Clin North Am. 2018 Nov;38(4):679-692

Authors: Workman AD, Kohanski MA, Cohen NA

Abstract
Chronic rhinosinusitis is a complex disease that exists along the inflammatory spectrum between types 1 and 2 inflammation. The classic phenotypic differentiation of chronic rhinosinusitis based on the presence or absence of inflammatory polyps remains one of the best differentiators of response to therapy. Development of biologics for the treatment of atopic disease and asthma and topical therapies for sinusitis have placed renewed emphasis on understanding the pathophysiology of polyp disease. Identification of key markers of polyposis will allow for better stratification of inflammatory polyp disease endotypes to objectively identify medical therapies and track response to treatment.

PMID: 30342588 [PubMed - in process]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2yR4iRO

Macrophages promote epithelial proliferation following infectious and non-infectious lung injury through a Trefoil factor 2-dependent mechanism.

Related Articles

Macrophages promote epithelial proliferation following infectious and non-infectious lung injury through a Trefoil factor 2-dependent mechanism.

Mucosal Immunol. 2018 Oct 18;:

Authors: Hung LY, Sen D, Oniskey TK, Katzen J, Cohen NA, Vaughan AE, Nieves W, Urisman A, Beers MF, Krummel MF, Herbert DR

Abstract
Coordinated efforts between macrophages and epithelia are considered essential for wound healing, but the macrophage-derived molecules responsible for repair are poorly defined. This work demonstrates that lung macrophages rely upon Trefoil factor 2 to promote epithelial proliferation following damage caused by sterile wounding, Nippostrongylus brasiliensis or Bleomycin sulfate. Unexpectedly, the presence of T, B, or ILC populations was not essential for macrophage-driven repair. Instead, conditional deletion of TFF2 in myeloid-restricted CD11cCre TFF2 flox mice exacerbated lung pathology and reduced the proliferative expansion of CD45- EpCAM+ pro-SPC+ alveolar type 2 cells. TFF2 deficient macrophages had reduced expression of the Wnt genes Wnt4 and Wnt16 and reconstitution of hookworm-infected CD11cCre TFF2flox mice with rWnt4 and rWnt16 restored the proliferative defect in lung epithelia post-injury. These data reveal a previously unrecognized mechanism wherein lung myeloid phagocytes utilize a TFF2/Wnt axis as a mechanism that drives epithelial proliferation following lung injury.

PMID: 30337651 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2CVxSKk

Personalized expression of bitter 'taste' receptors in human skin.

Related Articles

Personalized expression of bitter 'taste' receptors in human skin.

PLoS One. 2018;13(10):e0205322

Authors: Shaw L, Mansfield C, Colquitt L, Lin C, Ferreira J, Emmetsberger J, Reed DR

Abstract
The integumentary (i.e., skin) and gustatory systems both function to protect the human body and are a first point of contact with poisons and pathogens. These systems may share a similar protective mechanism because, as we show here, both human taste and skin cells express mRNA for bitter 'taste' receptors (TAS2Rs). We used gene-specific methods to measure mRNA from all known bitter receptor genes in adult human skin from freshly biopsied samples and from samples collected at autopsy from the Genotype-Tissue Expression project. Human skin expressed some but not all TAS2Rs, and for those that were expressed, the relative amounts differed markedly among individuals. For some TAS2Rs, mRNA abundance was related to presumed sun exposure based on the location from which the skin sample was collected (TAS2R14, TAS2R30, TAS2R42, and TAS2R60), sex (TAS2R3, TAS2R4, TAS2R8, TAS2R9, TAS2R14, and TAS2R60), and age (TAS2R5), although these effects were not large. These findings contribute to our understanding of extraoral expression of chemosensory receptors.

PMID: 30332676 [PubMed - in process]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2RXSMwL

Detection of Inflammation via Volatile Cues in Human Urine.

Related Articles

Detection of Inflammation via Volatile Cues in Human Urine.

Chem Senses. 2018 Sep 24;:

Authors: Gordon AR, Kimball BA, Sorjonen K, Karshikoff B, Axelsson J, Lekander M, Lundström JN, Olsson MJ

Abstract
Contagious disease is a major threat to survival, and the cost of relying on the immune system to defeat pathogens is high; therefore, behavioral avoidance of contagious individuals is arguably an adaptive strategy. Animal findings demonstrate the ability to detect and avoid sick individuals by the aid of olfactory cues, and a recent study indicated that human axillary odor also becomes more aversive as a function of immune activation. By injecting healthy human participants with lipopolysaccharide (0.6 ng/kg body weight) to experimentally induce inflammation, this study demonstrates that natural daily rhythms of urine odor-its perceived dimensions and volatile profile-are altered within hours of inflammation onset. Whereas healthy human urine decreases in averseness over the course of a single day, inflammation interrupts this process and results in an increased urine odor averseness and an altered volatile composition. These results support the notion that subtle and early cues of sickness may be detected and avoided, thereby complementing the immune system in its role of keeping us alive and healthy.

PMID: 30321293 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2PAV2bF

Detected Objects, Perceived Properties.

Related Articles

Detected Objects, Perceived Properties.

Chem Senses. 2018 Oct 09;:

Authors: Keller A

PMID: 30299465 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2Nzahjq

Perceived Properties Are Not Free-Floating.

Related Articles

Perceived Properties Are Not Free-Floating.

Chem Senses. 2018 Oct 09;:

Authors: Lindemann B

PMID: 30299463 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2OMIKQq

Massive expansion of bitter taste receptors in blind cavefish, Astyanax mexicanus.

Related Articles

Massive expansion of bitter taste receptors in blind cavefish, Astyanax mexicanus.

Chem Senses. 2018 Oct 05;:

Authors: Shiriagin V, Korsching SI

Abstract
A sensory deficit both at the individual and the species level can be compensated by increased acuity in other senses. The loss of vision in blind cavefish, Astyanaxmexicanus appears to be partially counterbalanced by enhanced chemosensory perception. Whether such improvement also involves adaptive changes in chemosensory receptor repertoires was unknown. The typical bitter taste receptor repertoire of teleost fishes is reported as three to five genes, much smaller than that of many terrestrial species. Interestingly, several fish species, e.g. mudskipper, have evolved a terrestric life style, but again it was unknown, whether this change in habitat is reflected in the size of gustatory receptor repertoires. We have searched the genomes of fifteen fish species and performed a thorough phylogenetic analysis to delineate their bitter taste receptor repertoires. We report no adaptation for four mudskipper species, which exhibit 3-4 bitter taste receptor genes, and thus a typical teleost repertoire, shaped by few gene losses and minor gene duplications from an ancestral repertoire of four genes. However, and in sharp contrast to all other teleost fish species analysed, blind cavefish possess over twenty intact bitter taste receptors plus several pseudogenes, rivalling the complexity of the human bitter taste receptor repertoire. The gene duplications giving rise to the current cavefish bitter taste receptor repertoire appear to have occurred well before the loss of vision, consistent with this increase in repertoire size constituting a preadaptive trait that conceivably could compensate to some extent for the lack of visual cues.

PMID: 30295711 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2y8zts3

Type of infant formula increases early weight gain and impacts energy balance: a randomized controlled trial.

Related Articles

Type of infant formula increases early weight gain and impacts energy balance: a randomized controlled trial.

Am J Clin Nutr. 2018 Oct 05;:

Authors: Mennella JA, Inamdar L, Pressman N, Schall JI, Papas MA, Schoeller D, Stallings VA, Trabulsi JC

Abstract
Background: Millions of infants are fed breast milk substitutes, and the type of infant formula can impact weight gain patterns.
Objective: We conducted a randomized controlled trial to determine the direct impact of 2 types of infant formula (cow milk formula, CMF; extensively protein hydrolyzed formula, EHF) on growth and energy balance.
Design: A racially diverse group of formula-fed infants (n = 113) were randomly assigned to either CMF or EHF from the age of 0.75 to 12.5 mo. At each monthly visit, anthropometric measures were obtained to determine growth z scores and weight gain velocity, and to categorize early weight gain patterns as rapid or nonrapid. Also, diet records were collected to determine energy from formula and other sources. Comprehensive assessments of energy balance (intake, expenditure, loss) were made at 0.75, 3.5, and 12.5 mo.
Results: Beginning 3 wk after randomization, CMF infants had significantly higher weight, but not length, z scores than did EHF infants, and this persisted after solid foods complemented the formula diet. On average, weight gain velocity from 0.75 to 4.5 mo was within the range of typically growing infants for both groups, yet velocity was 3.9 g/d greater for CMF infants (P = 0.002), who were more likely to be classified as an early rapid weight gainer, than EHF infants (46% compared with 18%; P = 0.007). Early differences in energy intake and fecal loss, yielding greater energy available for deposition among CMF infants, contributed to the differential weight gain patterns. There were no significant differences between the formula treatment groups in total energy expenditure or sleeping energy expenditure.
Conclusions: Among healthy infants, the type of formula impacted on early rapid weight gain patterns owing to energy intake and loss mechanisms. Research is needed to identify the macronutrients and other compositional constituents in EHF and breast milk that promote satiation and healthy weight gain during sensitive periods of development. This trial was registered at clinicaltrials.gov as: NCT01700205.

PMID: 30295700 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2PoqFFk

Long-term arsenite exposure induces testicular toxicity by redox imbalance, G2/M cell arrest and apoptosis in mice.

Long-term arsenite exposure induces testicular toxicity by redox imbalance, G2/M cell arrest and apoptosis in mice.

Toxicology. 2018 Sep 29;:

Authors: Zeng Q, Yi H, Huang L, An Q, Wang H

Abstract
Inorganic arsenic (iAs), a ubiquitous element and a natural drinking water contaminant, has been found to impair male reproductive function. However, the effect of long-term exposure to arsenic on testis damage and its underlying mechanisms still require further evaluation. In the study, male C57BL/6 mice (4 weeks) were treated with sodium arsenite at the doses of 5 or 50 ppm arsenic via drinking water for 180 days. Sperm count, histology in testes, oxidative stress biomarkers, cell cycle progress and apoptosis were assessed. Our results showed that arsenite seriously destroyed the structure of the testes and reduced the sperm count. Arsenite significantly decreased the activity of total superoxide dismutase (T-SOD) and glutathione (GSH) content but increased the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in testes. Furthermore, arsenite could induce G2/M phase arrest in testes, concurrent with a significant decrease in mRNA and protein levels of cdc2 and cyclin B1, the upregulation of p-cdc2, and an increase in mRNA levels of p53 and p21. Arsenite induced testicular apoptosis with a significant increase in Bax mRNA and protein levels, especially the caspase-3 activation. Testicular toxicity of the high dose group was stronger than that of the low dose group. In conclusion, testicular toxicity due to long-term exposure to arsenite may relate to oxidative damage, G2/M arrest and promoted apoptosis in the testes of mice, which contributed to the increased risk of spermatogenesis disorders and male infertility.

PMID: 30278210 [PubMed - as supplied by publisher]

from #ΓεύσηΌσφρηση via xlomafota13 on Inoreader https://ift.tt/2zOHuUr