scholarly journals Beyond Digestion: Can Animals Shape the Landscape According to Their Species–Specific Salivary Secretions?

Agriculture ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 817
Author(s):  
Maria Grazia Cappai ◽  
Sabine Aboling ◽  
Cecilia Dall’Aglio

Several functions are acknowledged for saliva secretion in different animal species following prehension and mastication of feed. Most of such are linked to the specific role of lubrication and softening of the bolus to allow taste perception and easy swallowing. Moreover, enzymatic components are produced in the saliva, some of which are destined to contribute to the digestion of different nutrients (to various extents according to animal species) and to exert antimicrobial activity (lysozyme). In addition, the buffering power and the virtuous recycle of water, electrolytes, and other metabolites are of particular importance for proper digestion and for nutrition–related aspects. Moreover, salivation appears to be involved in a number of other functions. Recent studies on salivary production and roles point to salivary glands as target organs of neuroendocrine regulation in response to many external stimuli coming from the outer world, for which feed still represents the chief external stimulus. Various animal species establish an adaptive strategy when coming into contact with different feeding stuffs and/or dietary substances by modifying both the composition and amount of saliva produced. In the light of recent updates, this review provides a focus on the functional roles of saliva secretions, showing the broad involvement of salivary response in several mechanisms beyond the digestive function and influencing feed selection.

2021 ◽  
Vol 22 (12) ◽  
pp. 6613
Author(s):  
Fernando C. Baltanás ◽  
Rósula García-Navas ◽  
Eugenio Santos

The SOS family of Ras-GEFs encompasses two highly homologous and widely expressed members, SOS1 and SOS2. Despite their similar structures and expression patterns, early studies of constitutive KO mice showing that SOS1-KO mutants were embryonic lethal while SOS2-KO mice were viable led to initially viewing SOS1 as the main Ras-GEF linking external stimuli to downstream RAS signaling, while obviating the functional significance of SOS2. Subsequently, different genetic and/or pharmacological ablation tools defined more precisely the functional specificity/redundancy of the SOS1/2 GEFs. Interestingly, the defective phenotypes observed in concomitantly ablated SOS1/2-DKO contexts are frequently much stronger than in single SOS1-KO scenarios and undetectable in single SOS2-KO cells, demonstrating functional redundancy between them and suggesting an ancillary role of SOS2 in the absence of SOS1. Preferential SOS1 role was also demonstrated in different RASopathies and tumors. Conversely, specific SOS2 functions, including a critical role in regulation of the RAS–PI3K/AKT signaling axis in keratinocytes and KRAS-driven tumor lines or in control of epidermal stem cell homeostasis, were also reported. Specific SOS2 mutations were also identified in some RASopathies and cancer forms. The relevance/specificity of the newly uncovered functional roles suggests that SOS2 should join SOS1 for consideration as a relevant biomarker/therapy target.


2010 ◽  
Vol 38 (1) ◽  
pp. 28-36 ◽  
Author(s):  
EDO KNEGTERING ◽  
HENNY J. VAN DER WINDT ◽  
ANTON J. M. SCHOOT UITERKAMP

SUMMARYSystematic knowledge about factors affecting the willingness of societies to conserve biodiversity is still scarce. This study investigates the role of body size in national decisions on wild animal species by analysing the average body sizes of the animal species subject to species-specific legislation in the Netherlands over the period 1857–1995. Three legal objectives were distinguished, namely ‘control’, ‘use’ and ‘protection’. For most taxa, average body sizes of species were found to differ significantly between legal objectives within a substantial number of subperiods analysed. Throughout the entire period examined, protected bird, mammal, fish and mollusc species were of smaller average body size than those subject to use legislation and protected bird, mammal and mollusc species were also smaller than those subject to control legislation most of the time. Protected insects were generally larger than those subject to control or use. For vertebrate taxa, average sizes of protected species increased over the time period selected for examination, suggesting that legislation initially excluded larger vertebrates from protection, possibly partly owing to demands to maintain use of these species. The results emphasize that conservation context is important, as other studies suggest that conservation policy generally favours larger species.


2019 ◽  
Vol 14 (7) ◽  
pp. 598-606
Author(s):  
Sarah Albogami

Background:: Regeneration is the process by which body parts lost as a result of injury are replaced, as observed in certain animal species. The root of regenerative differences between organisms is still not very well understood; if regeneration merely recycles developmental pathways in the adult form, why can some animals regrow organs whereas others cannot? In the regulation of the regeneration process as well as other biological phenomena, epigenetics plays an essential role. Objective:: This review aims to demonstrate the role of epigenetic regulators in determining regenerative capacity. Results:: In this review, we discuss the basis of regenerative differences between organisms. In addition, we present the current knowledge on the role of epigenetic regulation in regeneration, including DNA methylation, histone modification, lysine methylation, lysine methyltransferases, and the SET1 family. Conclusion:: An improved understanding of the regeneration process and the epigenetic regulation thereof through the study of regeneration in highly regenerative species will help in the field of regenerative medicine in future.


Author(s):  
Laura Empson

This book analyses the complex power dynamics and interpersonal politics that lie at the heart of leadership in professional organizations, such as accounting, law, and consulting firms, investment banks, hospitals, and universities. It is based on scholarly research into many of the world’s leading professional organizations across a range of sectors, including interviews with over 500 senior professionals in sixteen countries. Drawing on the latest academic theory to analyse exactly how professionals in organizations come together to create ‘leadership’, it provides new insights into how leaders lead when there is no traditional hierarchy to support them, their own authority is contingent, and they must constantly renegotiate relationships with relatively autonomous professional peers. It explores how leaders persuade highly intelligent, educated, and opinionated professionals to work together; how change happens within professional organizations; and why leaders so often fail. Part I introduces the concept of plural leadership, analysing how leaders establish and maintain their positions within leadership constellations, and the implications for governance in the context of collective or distributed leadership. Part II examines the complex, challenging relationships between professionals as they seek to influence their organizations, including the phenomena of leadership dyads, insecure overachievers, social control, and the rise of the management professional. Part III examines the shifts in the locus of power as professional organizations grow, adapt, and react to external stimuli such as mergers and acquisitions and economic crises. The conclusion identifies the paradoxes inherent in professional organizations and examines the role of leaders in attempting to reconcile them.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Arangasamy Yazhini ◽  
Narayanaswamy Srinivasan ◽  
Sankaran Sandhya

AbstractAfrotheria is a clade of African-origin species with striking dissimilarities in appearance and habitat. In this study, we compared whole proteome sequences of six Afrotherian species to obtain a broad viewpoint of their underlying molecular make-up, to recognize potentially unique proteomic signatures. We find that 62% of the proteomes studied here, predominantly involved in metabolism, are orthologous, while the number of homologous proteins between individual species is as high as 99.5%. Further, we find that among Afrotheria, L. africana has several orphan proteins with 112 proteins showing < 30% sequence identity with their homologues. Rigorous sequence searches and complementary approaches were employed to annotate 156 uncharacterized protein sequences and 28 species-specific proteins. For 122 proteins we predicted potential functional roles, 43 of which we associated with protein- and nucleic-acid binding roles. Further, we analysed domain content and variations in their combinations within Afrotheria and identified 141 unique functional domain architectures, highlighting proteins with potential for specialized functions. Finally, we discuss the potential relevance of highly represented protein families such as MAGE-B2, olfactory receptor and ribosomal proteins in L. africana and E. edwardii, respectively. Taken together, our study reports the first comparative study of the Afrotherian proteomes and highlights salient molecular features.


Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2036
Author(s):  
Luigi Marongiu ◽  
Markus Burkard ◽  
Sascha Venturelli ◽  
Heike Allgayer

Natural compounds such as essential oils and tea have been used successfully in naturopathy and folk medicine for hundreds of years. Current research is unveiling the molecular role of their antibacterial, anti-inflammatory, and anticancer properties. Nevertheless, the effect of these compounds on bacteriophages is still poorly understood. The application of bacteriophages against bacteria has gained a particular interest in recent years due to, e.g., the constant rise of antimicrobial resistance to antibiotics, or an increasing awareness of different types of microbiota and their potential contribution to gastrointestinal diseases, including inflammatory and malignant conditions. Thus, a better knowledge of how dietary products can affect bacteriophages and, in turn, the whole gut microbiome can help maintain healthy homeostasis, reducing the risk of developing diseases such as diverse types of gastroenteritis, inflammatory bowel disease, or even cancer. The present review summarizes the effect of dietary compounds on the physiology of bacteriophages. In a majority of works, the substance class of polyphenols showed a particular activity against bacteriophages, and the primary mechanism of action involved structural damage of the capsid, inhibiting bacteriophage activity and infectivity. Some further dietary compounds such as caffeine, salt or oregano have been shown to induce or suppress prophages, whereas others, such as the natural sweeter stevia, promoted species-specific phage responses. A better understanding of how dietary compounds could selectively, and specifically, modulate the activity of individual phages opens the possibility to reorganize the microbial network as an additional strategy to support in the combat, or in prevention, of gastrointestinal diseases, including inflammation and cancer.


2021 ◽  
Vol 22 (9) ◽  
pp. 4637
Author(s):  
Daniel Barth ◽  
Andreas Lückhoff ◽  
Frank J. P. Kühn

The human apoptosis channel TRPM2 is stimulated by intracellular ADR-ribose and calcium. Recent studies show pronounced species-specific activation mechanisms. Our aim was to analyse the functional effect of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), commonly referred to as PIP2, on different TRPM2 orthologues. Moreover, we wished to identify the interaction site between TRPM2 and PIP2. We demonstrate a crucial role of PIP2, in the activation of TRPM2 orthologues of man, zebrafish, and sea anemone. Utilizing inside-out patch clamp recordings of HEK-293 cells transfected with TRPM2, differential effects of PIP2 that were dependent on the species variant became apparent. While depletion of PIP2 via polylysine uniformly caused complete inactivation of TRPM2, restoration of channel activity by artificial PIP2 differed widely. Human TRPM2 was the least sensitive species variant, making it the most susceptible one for regulation by changes in intramembranous PIP2 content. Furthermore, mutations of highly conserved positively charged amino acid residues in the membrane interfacial cavity reduced the PIP2 sensitivity in all three TRPM2 orthologues to varying degrees. We conclude that the membrane interfacial cavity acts as a uniform PIP2 binding site of TRPM2, facilitating channel activation in the presence of ADPR and Ca2+ in a species-specific manner.


Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Mojca Jensterle ◽  
Simona Ferjan ◽  
Tadej Battelino ◽  
Jernej Kovač ◽  
Saba Battelino ◽  
...  

Abstract Background Preclinical studies demonstrated that glucagon-like peptide 1 (GLP-1) is locally synthesized in taste bud cells and that GLP-1 receptor exists on the gustatory nerves in close proximity to GLP-1-containing taste bud cells. This local paracrine GLP-1 signalling seems to be specifically involved in the perception of sweets. However, the role of GLP-1 in taste perception remains largely unaddressed in clinical studies. Whether any weight-reducing effects of GLP-1 receptor agonists are mediated through the modulation of taste perception is currently unknown. Methods and analysis This is an investigator-initiated, randomized single-blind, placebo-controlled clinical trial. We will enrol 30 women with obesity and polycystic ovary syndrome (PCOS). Participants will be randomized in a 1:1 ratio to either semaglutide 1.0 mg or placebo for 16 weeks. The primary endpoints are alteration of transcriptomic profile of tongue tissue as changes in expression level from baseline to follow-up after 16 weeks of treatment, measured by RNA sequencing, and change in taste sensitivity as detected by chemical gustometry. Secondary endpoints include change in neural response to visual food cues and to sweet-tasting substances as assessed by functional MRI, change in body weight, change in fat mass and change in eating behaviour and food intake. Discussion This is the first study to investigate the role of semaglutide on taste perception, along with a neural response to visual food cues in reward processing regions. The study may identify the tongue and the taste perception as a novel target for GLP-1 receptor agonists. Ethics and disseminations The study has been approved by the Slovene National Medical Ethics Committee and will be conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. Results will be submitted for publication in an international peer-reviewed scientific journal. Trial registration ClinicalTrials.govNCT04263415. Retrospectively registered on 10 February 2020


Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 460
Author(s):  
Mohammed Hamed Alqarni ◽  
Ahmed Ibrahim Foudah ◽  
Magdy Mohamed Muharram ◽  
Nikolaos E. Labrou

Sirtuins (SIRTs) are nicotinamide adenine dinucleotide-dependent histone deacetylases that incorporate complex functions in the mechanisms of cell physiology. Mammals have seven distinct members of the SIRT family (SIRT1-7), which play an important role in a well-maintained network of metabolic pathways that control and adapt the cell to the environment, energy availability and cellular stress. Until recently, very few studies investigated the role of SIRTs in modulating viral infection and progeny. Recent studies have demonstrated that SIRT1 and SIRT2 are promising antiviral targets because of their specific connection to numerous metabolic and regulatory processes affected during infection. In the present review, we summarize some of the recent progress in SIRTs biochemistry and their emerging function as antiviral targets. We also discuss the potential of natural polyphenol-based SIRT modulators to control their functional roles in several diseases including viral infections.


Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 831
Author(s):  
Patrycja Burzyńska ◽  
Łukasz F. Sobala ◽  
Krzysztof Mikołajczyk ◽  
Marlena Jodłowska ◽  
Ewa Jaśkiewicz

Carbohydrates have long been known to mediate intracellular interactions, whether within one organism or between different organisms. Sialic acids (Sias) are carbohydrates that usually occupy the terminal positions in longer carbohydrate chains, which makes them common recognition targets mediating these interactions. In this review, we summarize the knowledge about animal disease-causing agents such as viruses, bacteria and protozoa (including the malaria parasite Plasmodium falciparum) in which Sias play a role in infection biology. While Sias may promote binding of, e.g., influenza viruses and SV40, they act as decoys for betacoronaviruses. The presence of two common forms of Sias, Neu5Ac and Neu5Gc, is species-specific, and in humans, the enzyme converting Neu5Ac to Neu5Gc (CMAH, CMP-Neu5Ac hydroxylase) is lost, most likely due to adaptation to pathogen regimes; we discuss the research about the influence of malaria on this trait. In addition, we present data suggesting the CMAH gene was probably present in the ancestor of animals, shedding light on its glycobiology. We predict that a better understanding of the role of Sias in disease vectors would lead to more effective clinical interventions.


Sign in / Sign up

Export Citation Format

Share Document