The Influence of (Poly)phenol Intake in Saliva Proteome: Short- and Medium-Term Effects of Apple.

The relationship between salivary proteome and dietary habits was studied in previous works, where a relationship between salivary proteins like cystatins and polyphenol/tannin levels in diet was observed. However, it remains to be elucidated if this association results from an effect of polyphenol-rich food ingestion on saliva composition. The aim of this work was to test the effects of apple intake on the saliva proteome, both in the short and medium term (after 4 days of continuous intake). By incubating saliva samples with apple phenolic-rich extract, protein bands containing α-amylase, S-type cystatins, and proline-rich proteins (PRPs) appeared in the fraction that precipitated, showing the potential of these (poly)phenols to precipitate salivary proteins. Among these, it was salivary cystatins that presented changes in their levels both in the saliva samples collected immediately after apple intake and in the ones collected after 4 days of intake of an extra amount of apple. These results support the thought that intake is reflected in the salivary proteome. The effect of a polyphenol-rich food, like the apple, on salivary cystatin levels is in line with results observed in animal models and, due to the involvement of these proteins in oral food perception, it would be interesting to explore in future studies the effect of these changes on sensory perception and acceptance of polyphenol-rich food.

Apoptosis-50 Years after Its Discovery.

Apoptosis is a programmed cell death routine that plays an essential role in several biological processes, namely, embryonic development, tissue homeostasis, and immune response [...].

Effect of thermal and chemical treatments used for SARS-COV-2 inactivation in the measurement of saliva analytes.

The present study aims to assess the effects of thermal and chemical inactivating procedures, that can be used for SARS-CoV-2 inactivation, on different salivary analytes. SDS-Polyacrylamide Gel Electrophoresis (SDS-PAGE) protein profile and a panel of 25 specific biomarkers of oxidative status, stress, metabolism and tissue damage were evaluated in samples subjected to different treatments: thermal (65 °C or 92 °C) and chemical with detergents [sodium dodecyl sulphate (SDS), Triton X-100 or NP-40]. Salivary SDS-PAGE profile was most affected by heating at 92 °C, with three and two protein bands decreasing and increasing their expression levels, respectively. This treatment also affected the results of several enzymes, with some of them being also affected by heating at 65 °C and incubation with SDS. The use of Triton X-100 or NP-40 resulted in increased values of cortisol, triglycerides and glucose, not affecting the other tested biomarkers. The present results will help researchers and clinicians to select the best protocols to work in safe conditions with saliva, taking into account the target analyte planned to be measured.

Models for Oral Biology Research.

Oral biology is a scientific field that involves several disciplines, such as anatomy, cellular and molecular biology, genetics, microbiology, immunology, biochemistry, pharmacology, physiology and pathology [...].

Changes in food behavior during the first lockdown of COVID-19 pandemic: A multi-country study about changes in eating habits, motivations, and food-related behaviors.

The COVID-19 pandemic resulted in severe, unprecedented changes affecting the world population. Restrictions in mobility, social distancing measures, and the persistent social alarm, during the first period of pandemic, resulted in dramatic lifestyle changes and affected physical and psychological wellbeing on a global scale. An international research team was constituted to develop a study involving different countries about eating motivations, dietary habits and behaviors related with food intake, acquisition, and preparation. This study presents results of an online survey, carried out during the first lockdown, in 2020, assessing food-related behavior and how people perceived them to change, comparatively to the period preceding the COVID-19 outbreak. A total of 3332 responses, collected from 16 countries, were considered for analysis [72.8% in Europe, 12.8% in Africa, 2.2% in North America (USA) and 12.2% in South America]. Results suggest that the main motivations perceived to drive food intake were familiarity and liking. Two clusters were identified, based on food intake frequency, which were classified as "healthier" and "unhealthier". The former was constituted by individuals with higher scholarity level, to whom intake was more motivated by health, natural concerns, and weight control, and less by liking, pleasure or affect regulation. The second cluster was constituted by individuals with a higher proportion of male and intake more influenced by affect-related motivations. During this period, a generalized lower concern with the convenience attributes of foods was noted (namely, choice of processed products and fast-food meals), alongside an increase in time and efforts dedicated to home cooking. Understanding the main changes and their underlying motivations in a time of unprecedented crisis is of major importance, as it provides the scientific support that allows one to anticipate the implications for the future of the global food and nutrition system and, consequently, to take the appropriate action.

Covid-19: Signs and symptoms related to the feeding behavior.

COVID-19 reached pandemic level in March 2020 and the number of confirmed cases continued to increase worldwide. The clinical course of the disease has not yet been fully characterized, and some specific symptoms related to smell, taste, and feeding behavior require further examination. The present study aimed to assess the presence of symptoms related to the feeding behavior occurred during and/or after COVID-19 in adults residing in Portugal and to link them to disease severity using a multivariate approach. Data were collected from May to September 2020, through a questionnaire answered online containing questions about general and specific symptoms before, during and after COVID-19. 362 participants were included: 201 were symptomatic, being 15 hospitalized and 186 non-hospitalized. Cluster analysis grouped the symptomatic non-hospitalized participants as mild and severe cases. For these patients, the most frequent symptoms related to the feeding process were smell disorders in 40% and 62%, taste disorders in 37% and 60%, and dry mouth, in 23% and 48% of the mild and severe cases, respectively. Dry mouth was significantly associated with difficulty to swallow, pain during swallow, choking when eating or drinking, and preference for mushy/pasty foods (p < 0.01; Chi-squared test). Among the severe cases, the incidence of coughing during the meal (31%), difficulty (19%) and pain during swallow (17%), preference for mushy/pasty foods (10%) and choking when eating or drinking (6%) were clinically relevant and may indicate the presence of swallowing disorders. This group also showed a higher frequency of general symptoms, such as fever, headache, abdominal pain, tiredness, diarrhea, nausea, and shortness of breath (p < 0.05; Chi-squared test). Smell disorders, taste disorders and dry mouth were the most frequent symptoms related to the feeding behavior for both mild and severe cases. Dry mouth was significantly associated with swallowing difficulties and future research should investigate it as a frequent symptom and as a predictive of the presence of eating and swallowing disorders in COVID-19 cases.

How Individual Variations in the Perception of Basic Tastes and Astringency Relate with Dietary Intake and Preferences for Fruits and Vegetables.

Background: Oral food perception plays a major role in food acceptance, although the way it relates with food preferences and final choices in adults is still debatable. The objective of the present study was to assess the relationship between gustatory function, dietary habits and fruit and vegetable preferences. Methods: Recognition thresholds, suprathreshold and hedonics were accessed for sweet, bitter, sour, salty and astringency in 291 adult participants. A Food Frequency Questionnaire (FFQ) and a questionnaire for assessment of preferences for individual fruit and vegetables were filled by the participants. Results: Three clusters were obtained: "most sensitive", "less sensitive" and "less sensitive only for sour". The less sensitive cluster showed lower preferences for fruit and vegetables and higher intake of sweets and fast foods, whereas higher preferences for sweet veggies were observed in the "most sensitive" cluster. Basic tastes and astringency hedonics did not associate with fruit and vegetable preferences, but the sensitivity for these oral sensations did. Conclusions: Taste and astringency sensitivities are related with the preference for fruit and vegetables, being also associated with some dietary habits. The effectiveness of the strategies to promote plant-based healthy food consumption may benefit from the knowledge of individuals' gustatory function.

Use of Saliva for Diagnosis and Monitoring the SARS-CoV-2: A General Perspective.

In this report, updated information and future perspectives about the use of saliva as a sample for laboratory analysis of the Covid-19 are highlighted. Saliva can be used for the direct detection of the SARS-CoV-2 virus, the quantification of the specific immunoglobulins produced against it, and for the evaluation of the non-specific, innate immune response of the patient. Moreover, a deeper knowledge of potential changes in the saliva proteome in this disease may allow the identification of new diagnostic and prognostic biomarkers, or even help our understanding of the mechanisms associated with the disease. With the development of appropriate sample collection and processing methods and the use of adequate assays, saliva can provide useful clinical information about the disease and could be potentially included in guidelines for sample collection for the diagnosis, disease management, and control of Covid-19.

Comparative proteomic analysis of saliva from dogs with and without obesity-related metabolic dysfuntion.

Dogs develop only some of the components of the human metabolic syndrome (MetS). Thus, in order to study possible MetS-related alterations in dogs, human MetS criteria were adapted to define canine MetS or so-called obesity-related metabolic dysfunction (ORMD). The main objective of this study was to identify changes in the salivary proteome of obese dogs with ORMD in comparison with obese dogs without ORMD which may constitute potential salivary biomarkers for assessing ORMD. In a first phase, 12 adult obese dogs with ORMD (N = 6) and without ORMD (N = 6) were included in the study. Subsequently, and with the aim of validating and strengthening the results, additional 12 obese dogs (6 with and 6 without ORMD) were tested in an independent experiment following the same protocol. Saliva samples were subjected to a quantitative proteomics analysis and the levels of nine salivary proteins were found to be significantly different between groups, among them those which had greatest fold-change were proteins involved in glycolysis and oxidative stress. In conclusion, despite metabolic syndrome to include different combinations of diseases, the observation of differences in salivary proteome suggests a potential of this fluid to understand the pathophysiology of the disease. SIGNIFICANCE: This is the first study evaluating proteomes of saliva in dogs, as a non invasive sample, in order to increase knowledge about the metabolic/physiopathological changes related to obesity-related metabolic dysfunction (ORMD) together with the identification of potential biomarkers for its diagnosis. As approximately 20% of dogs with naturally occurring obesity were described to suffer ORMD associated with insulin resistance and hypoadiponectinemia, the fact that indicate possible links between ORMD and associated diseases.

Effects of hyperleptinemia in rat saliva composition, histology and ultrastructure of the major salivary glands.

OBJECTIVE: To study the effect of the satiety hormone, leptin, in saliva proteome and salivary gland histology and ultrastructure. DESIGN: Increases in blood leptin levels were induced through mini-pump infusion in male Wistar rats, during a period of 7 days. Saliva was collected before and at the end of the experimental period, for proteomic analysis, and major salivary glands were collected, at the end, for biochemical, histological and ultrastructural analysis. RESULTS: Immunohistochemistry revealed the presence of leptin receptors in major salivary glands. Salivary amylase levels and enzymatic activity were decreased in saliva, whereas the enzymatic activity of this protein was increased in the cytosol of parotid gland cells. Transmission electron microscopy allowed the observation of high number of electron-dense granules in cytosol of parotid acinar cells, from leptin treated animals. CONCLUSIONS: Increased levels of plasmatic leptin result in changes in saliva composition and salivary glands function. To our knowledge, this is the first study providing evidences for a potential role of leptin in salivary gland secretion and saliva composition. An understanding of how appetite/satiety factors influence saliva composition and how this composition influences food processing in mouth may be relevant in understanding ingestivebehaviour.

Detection of 70 kDa heat shock protein in the saliva of dairy cows.

This Research Communication describes, for the first time, the detection of HSP70 in saliva of dairy cows. Thermal stress is a major environmental stress that limits animal growth, metabolism, and productivity. The cellular response to heat stress involves the synthesis of heat shock proteins (HSPs), presumably to protect the functional stability of cells at increasing temperatures. HSP70 has been found to be present in cattle blood serum and may also be present in other secretory fluids, such as saliva, as already observed in humans. The aim of this study was to detect heat shock protein HSP70 in bovine saliva. Saliva samples were taken from higher- (n = 5) and lower milk producing (n = 5) Holstein-Friesian cows in summer and in winter for the detection of HSP70. HSP70 concentrations were assayed using the ELISA technique. Salivary HSP70 concentrations ranged from 0·524 to 12·174 ng/ml in cows. Higher salivary HSP70 concentrations were significantly associated with higher milk production and higher environmental temperature, but not with rectal temperature.

Characterization of hypertrophic osteoarthropathy in an identified skeleton from Évora, Portugal, using combined and comparative morphology and microscopy.

Hypertrophic osteoarthropathy (HOA) is a bone pathology that can be associated with a number of focal or systemic diseases, particularly those affecting the respiratory system. HOA is characterized by proliferative periostosis of the long bones, especially in their distal and periarticular regions. This report presents a probable case of HOA in the skeleton of an elderly Portuguese male from Évora, Portugal, who died in 1970. The skeleton was evaluated by morphological, radiological, and histological methods. We found bilateral periosteal proliferation of the tubular bones, remodeling of the phalanges of the feet, and new bone formation on rib visceral surfaces. Bone alterations are more severe on the left tibia and fibula, where lesions display a 'tree bark' appearance, leading to severe thickening of the diaphysis. Microscopically, we observed deposition of porous woven bone. Our evaluation also considers a differential diagnosis of the lesions, which includes melorheostosis, hypervitaminosis A, fluorosis, thyroid acropachy, tuberculosis, and treponematosis.

Effects of high-fat diet on salivary α-amylase, serum parameters and food consumption in rats.

Salivary α-amylase, a major protein in saliva, has been described as a marker of sympathetic nervous system activity, hence for metabolic energy balance. In this context, its expression in overweight and obesity is of interest. Rats fed with a diet enriched with sunflower oil differentially gained weight yielding two subgroups according to their susceptibility (OP) or resistance (OR) to obesity. Elevated plasmatic levels of leptin in the OP subgroup and altered plasmatic lipid profiles (lower triglycerides and higher total cholesterol/high-density lipoprotein (HDL) ratio compared to controls) in the OR subgroup were observed. Animals from the OP subgroup presented higher α-amylase expression and activity even prior to the dietary treatment, suggesting that this salivary protein may constitute a putative indicator of susceptibility for fat tissue accumulation. After 18 weeks of high-fat diet consumption, salivary α-amylase levels did not significantly change in the OP subgroup, but increased 3-fold in the OR subgroup. The increase in α-amylase levels for the latter might represent an adaptation to lower starch intake. These results suggest that salivary α-amylase secretion might be useful to predict susceptibility for weight gain induced by high-fat diet consumption.

A new piezoelectric actuator induces bone formation in vivo: a preliminary study.

This in vivo study presents the preliminary results of the use of a novel piezoelectric actuator for orthopedic application. The innovative use of the converse piezoelectric effect to mechanically stimulate bone was achieved with polyvinylidene fluoride actuators implanted in osteotomy cuts in sheep femur and tibia. The biological response around the osteotomies was assessed through histology and histomorphometry in nondecalcified sections and histochemistry and immunohistochemistry in decalcified sections, namely, through Masson's trichrome, and labeling of osteopontin, proliferating cell nuclear antigen, and tartrate-resistant acid phosphatase. After one-month implantation, total bone area and new bone area were significantly higher around actuators when compared to static controls. Bone deposition rate was also significantly higher in the mechanically stimulated areas. In these areas, osteopontin increased expression was observed. The present in vivo study suggests that piezoelectric materials and the converse piezoelectric effect may be used to effectively stimulate bone growth.

The effect of tannins on Mediterranean ruminant ingestive behavior: the role of the oral cavity.

Sheep, cattle and goat are domestic ruminants of significant economic interest in the Mediterranean region. Although sharing the same pasture ranges, they ingest different plants and plant parts and, consequently different levels of tannins. This suggests an ability to detect and adapt ingestion according to animal physiological limits of tolerance for plant secondary metabolites. This review will detail the effects of dietary tannins on feeding behavior, and the role of the oral cavity in this process, with focus on such ruminant species. The role of salivary protein profile in tannin perception in the oral cavity, and as a defense mechanism, will be discussed.

Integrated biomimetic carbon nanotube composites for in vivo systems.

As interest in using carbon nanotubes for developing biologically compatible systems continues to grow, biological inspiration is stimulating new directions for in vivo approaches. The ability to integrate nanotechnology-based systems in the body will provide greater successes if the implanted material is made to mimic elements of the biological milieu especially through tuning physical and chemical characteristics. Here, we demonstrate the highly successful capacity for in vivo implantation of a new carbon nanotube-based composite that is, itself, integrated with a hydroxyapatite-polymethyl methacrylate to create a nanocomposite. The success of this approach is grounded in finely tailoring the physical and chemical properties of this composite for the critical demands of biological integration. This is accomplished through controlling the surface modification scheme, which affects the interactions between carbon nanotubes and the hydroxyapatite-polymethyl methacrylate. Furthermore, we carefully examine cellular response with respect to adhesion and proliferation to examine in vitro compatibility capacity. Our results indicate that this new composite accelerates cell maturation through providing a mechanically competent bone matrix; this likely facilitates osteointegration in vivo. We believe that these results will have applications in a diversity of areas including carbon nanotube, regeneration, chemistry, and engineering research.

Comparison of electrophoretic protein profiles from sheep and goat parotid saliva.

Saliva provides a medium for short-term adaptation to changes in diet composition, namely, the presence of plant secondary metabolites. Salivary proteins have biological functions that have particular influence on oral homeostasis, taste, and digestive function. Some salivary proteins, such as proline-rich proteins, are present in browsers but absent in grazers. Despite the significance of salivary proteins, their expression patterns in many herbivores are unknown. We investigated the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile of parotid salivary proteins from two domesticated species, one a grazer, the sheep, Ovis aries, and the other a mixed feeder, the goat, Capra hircus, both fed on the same conventional diet. With 12.5% polyacrylamide linear gels, we observed uniform patterns of salivary proteins within the two species. In the goat profile, 21 major bands were observed, and 19 in the sheep profile. Each band was subjected to peptide mass fingerprinting for purposes of identification, allowing for 16 successful protein identifications. Marked differences were observed between the species in the region of 25-35 kDa molecular weights: one band was present in significantly different intensities; three bands were present only in goats; and one band was present only in sheep. This is the first report of a comparison of the protein salivary composition of sheep and goats and suggests that future research should be conducted to reveal a physiological function for salivary proteins related to the differences in feeding behavior of these species.