scholarly journals Expression of Taste Receptor 2 Subtypes in Human Testis and Sperm

2020 ◽  
Vol 9 (1) ◽  
pp. 264 ◽  
Author(s):  
Laura Governini ◽  
Bianca Semplici ◽  
Valentina Pavone ◽  
Laura Crifasi ◽  
Camilla Marrocco ◽  
...  

Taste receptors (TASRs) are expressed not only in the oral cavity but also throughout the body, thus suggesting that they may play different roles in organ systems beyond the tongue. Recent studies showed the expression of several TASRs in mammalian testis and sperm, indicating an involvement of these receptors in male gametogenesis and fertility. This notion is supported by an impaired reproductive phenotype of mouse carrying targeted deletion of taste receptor genes, as well as by a significant correlation between human semen parameters and specific polymorphisms of taste receptor genes. To better understand the biological and thus clinical significance of these receptors for human reproduction, we analyzed the expression of several members of the TAS2Rs family of bitter receptors in human testis and in ejaculated sperm before and after in vitro selection and capacitation. Our results provide evidence for the expression of TAS2R genes, with TAS2R14 being the most expressed bitter receptor subtype in both testis tissue and sperm cells, respectively. In addition, it was observed that in vitro capacitation significantly affects both the expression and the subcellular localization of these receptors in isolated spermatozoa. Interestingly, α-gustducin and α-transducin, two Gα subunits expressed in taste buds on the tongue, are also expressed in human spermatozoa; moreover, a subcellular redistribution of both G protein α-subunits to different sub-compartments of sperm was registered upon in vitro capacitation. Finally, we shed light on the possible downstream transduction pathway initiated upon taste receptor activation in the male reproductive system. Performing ultrasensitive droplets digital PCR assays to quantify RNA copy numbers of a distinct gene, we found a significant correlation between the expression of TAS2Rs and TRPM5 (r = 0.87), the cation channel involved in bitter but also sweet and umami taste transduction in taste buds on the tongue. Even if further studies are needed to clarify the precise functional role of taste receptors for successful reproduction, the presented findings significantly extend our knowledge of the biological role of TAS2Rs for human male fertility.

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Menizibeya O. Welcome ◽  
Nikos E. Mastorakis ◽  
Vladimir A. Pereverzev

Sweet taste receptors are transmembrane protein network specialized in the transmission of information from special “sweet” molecules into the intracellular domain. These receptors can sense the taste of a range of molecules and transmit the information downstream to several acceptors, modulate cell specific functions and metabolism, and mediate cell-to-cell coupling through paracrine mechanism. Recent reports indicate that sweet taste receptors are widely distributed in the body and serves specific function relative to their localization. Due to their pleiotropic signaling properties and multisubstrate ligand affinity, sweet taste receptors are able to cooperatively bind multiple substances and mediate signaling by other receptors. Based on increasing evidence about the role of these receptors in the initiation and control of absorption and metabolism, and the pivotal role of metabolic (glucose) regulation in the central nervous system functioning, we propose a possible implication of sweet taste receptor signaling in modulating cognitive functioning.


2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.


Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 667
Author(s):  
Meera Krishnan ◽  
Sahil Kumar ◽  
Luis Johnson Kangale ◽  
Eric Ghigo ◽  
Prasad Abnave

Adult stem cells (ASCs) are the undifferentiated cells that possess self-renewal and differentiation abilities. They are present in all major organ systems of the body and are uniquely reserved there during development for tissue maintenance during homeostasis, injury, and infection. They do so by promptly modulating the dynamics of proliferation, differentiation, survival, and migration. Any imbalance in these processes may result in regeneration failure or developing cancer. Hence, the dynamics of these various behaviors of ASCs need to always be precisely controlled. Several genetic and epigenetic factors have been demonstrated to be involved in tightly regulating the proliferation, differentiation, and self-renewal of ASCs. Understanding these mechanisms is of great importance, given the role of stem cells in regenerative medicine. Investigations on various animal models have played a significant part in enriching our knowledge and giving In Vivo in-sight into such ASCs regulatory mechanisms. In this review, we have discussed the recent In Vivo studies demonstrating the role of various genetic factors in regulating dynamics of different ASCs viz. intestinal stem cells (ISCs), neural stem cells (NSCs), hematopoietic stem cells (HSCs), and epidermal stem cells (Ep-SCs).


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Neil N. Patel ◽  
Alan D. Workman ◽  
Noam A. Cohen

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.


Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3127
Author(s):  
Bianca Semplici ◽  
Francesca Paola Luongo ◽  
Sofia Passaponti ◽  
Claudia Landi ◽  
Laura Governini ◽  
...  

Bitter taste receptors (TAS2RS) expression is not restricted to the oral cavity and the presence of these receptors in the male reproductive system and sperm provides insights into their possible role in human reproduction. To elucidate the potential role of TAS2Rs in the female reproductive system, we investigated the expression and localization of bitter taste receptors and the components of signal transduction cascade involved in the pathway of taste receptors in somatic follicular cells obtained from women undergoing assisted reproductive techniques. We found that TAS2R genes are expressed in both cumulus (CCs) and granulosa (GCs) cells, with TAS2R14 being the most highly expressed bitter receptor subtype. Interestingly, a slight increase in the expression of TAS2R14 and TAS2R43 was shown in both GCs and CCs in young women (p < 0.05), while a negative correlation may be established between the number of oocytes collected at the pickup and the expression of TAS2R43. Regarding α-gustducin and α-transducin, two Gα subunits expressed in the taste buds on the tongue, we provide evidence for their expression in CCs and GCs, with α-gustducin showing two additional isoforms in GCs. Finally, we shed light on the possible downstream transduction pathway initiated by taste receptor activation in the female reproductive system. Our study, showing for the first time the expression of taste receptors in the somatic ovarian follicle cells, significantly extends the current knowledge of the biological role of TAS2Rs for human female fertility.


2018 ◽  
Vol 4 ◽  
Author(s):  
Yanli Jiao ◽  
Yu Wang

Sweet taste, one of the five basic taste qualities, is not only important for evaluation of food quality, but also guides the dietary food choices of animals. Sweet taste involves a variety of chemical compounds and structures, including natural sugars, sugar alcohols, natural and artificial sweeteners, and sweet-tasting proteins. The preference for sweetness has induced the over-consumption of sugar, contributing to certain prevailing health problems, such as obesity, diabetes and cardiovascular disease. Non-nutritive sweeteners, including natural and synthetic sweeteners, and sweet-tasting proteins have been added to foods to reduce the caloric intake from sugar, but many of these sugar substitutes induce an off-taste or after taste that negatively impacts any pleasure derived from the sweet taste. Sweet taste is detected by sweet taste receptor, that also play an important role in the metabolic regulation of the body, such as glucose homeostasis and incretin hormone secretion. In this review, the role of sweet tastants and the sweet taste receptors involved in sweetness perception, and their effect on obesity and diabetes are summarized. Sweet taste enhancement, as a new way to solve the over-consumption of sugar, is discussed in this contribution. Sweet taste enhancers can bind with sweet tastans to potentiate the sweetness of food without producing any taste by itself. Various type of sweet taste enhancers, including synthetic compounds, food-processed substances and aroma compounds, are summarized. Notably, few natural, non-volatile compounds have been identified as sweetness enhancers.


2019 ◽  
Vol 221 (9) ◽  
pp. 1542-1553 ◽  
Author(s):  
Fabrício O Souto ◽  
Fernanda V S Castanheira ◽  
Silvia C Trevelin ◽  
Braulio H F Lima ◽  
Guilherme Cesar Martelossi Cebinelli ◽  
...  

Abstract Background Liver X receptors (LXRs) are nuclear receptors activated by oxidized lipids and were previously implicated in several metabolic development and inflammatory disorders. Although neutrophils express both LXR-α and LXR-β, the consequences of their activation, particularly during sepsis, remain unknown. Methods We used the model of cecal ligation and puncture (CLP) to investigate the role of LXR activation during sepsis. Results In this study, we verified that LXR activation reduces neutrophil chemotactic and killing abilities in vitro. Mice treated with LXR agonists showed higher sepsis-induced mortality, which could be associated with reduced neutrophil infiltration at the infectious foci, increased bacteremia, systemic inflammatory response, and multiorgan failure. In contrast, septic mice treated with LXR antagonist showed increased number of neutrophils in the peritoneal cavity, reduced bacterial load, and multiorgan dysfunction. More important, neutrophils from septic patients showed increased ABCA1 messenger ribonucleic acid levels (a marker of LXR activation) and impaired chemotactic response toward CXCL8 compared with cells from healthy individuals. Conclusions Therefore, our findings suggest that LXR activation impairs neutrophil functions, which might contribute to poor sepsis outcome.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Veronika Günther ◽  
Ibrahim Alkatout ◽  
Corinna Fuhs ◽  
Ali Salmassi ◽  
Liselotte Mettler ◽  
...  

Cytokines are key modulators of the immune system and play an important role in the ovarian cycle. IL-18 levels in serum and follicular fluid were analyzed in women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment. The cohort study group consisted of 90 women, who were undergoing IVF or ICSI. The body mass index (BMI) was determined in all patients; IL-18 levels were measured in follicular fluid and serum. IL-18 levels in serum were significantly higher than those in follicular fluid. The median level in serum was 162.75 (80.21) pg/mL and that in follicular fluid, 138.24 (91.78) pg/mL. Women undergoing IVF treatment had lower IL-18 levels in serum (median, 151.19 (90.73) pg/mL) than those treated with ICSI (median, 163.57 (89.97) pg/mL). The correlation between IL-18 levels in serum and BMI was statistically significant, as well as the correlation between IL-18 levels in follicular fluid and ovarian stimulation response (p=0.003). IL-18 was correlated with the response to ovarian stimulation and was the reason for successful pregnancy after IVF or ICSI treatment. Among other cytokines, IL-18 appears to be a promising prognostic marker of success in reproductive treatment and should be evaluated as such in further prospective studies.


2011 ◽  
Vol 84 (2) ◽  
pp. 239-248 ◽  
Author(s):  
Alan A. Sneddon

Selenium (Se) is an important dietary micronutrient required for sustaining optimal health. Se is incorporated into proteins, many of which are antioxidants that protect the body against oxidative damage. As oxidative damage may contribute to the development of chronic diseases including cardiovascular disease (CVD), Se has been proposed to provide a protective role against this disease. Studies in vitro and in animals continue to provide increasing insight into the role of Se in promoting vascular health and ameliorating CVD. Se within vascular cells limits the adhesion together of such cells, an important early step in the development of vascular disease. Organic forms of Se may also afford vascular cells greater protection against oxidative challenge compared to inorganic forms. Nevertheless, current studies in humans investigating the relationship between Se and CVD have so far proved equivocal; larger randomized trials with different Se exposures in populations spanning the broad physiological Se status are needed to determine the criteria whereby Se may influence CVD outcome within different populations. Further studies are also needed to explore the effects of different Se species and the role of different selenoprotein genotypes in modifying Se status and their resultant impact on cardiovascular function.


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