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Rajesh K, Sundar S, Rajaraman V, Ramadoss R, Venugopalan S. Assessment of Oral Masticatory Muscle Activity With Different Chewing Gums: A Cross-Sectional Study Based on Electromyogram Analysis. Cureus 2024; 16:e56849. [PMID: 38659520 PMCID: PMC11042667 DOI: 10.7759/cureus.56849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 03/24/2024] [Indexed: 04/26/2024] Open
Abstract
BACKGROUND Facial muscles, particularly those involved in mastication, play a pivotal role in the chewing process. Despite their influence on chewing, these muscles undergo alterations during mastication. Examining the relationship between chewed substances and muscle activity can provide insights into various pathological processes and aid in the development of therapeutic chewing techniques. AIM This study aimed to evaluate the impact of different commercially available chewing gums on the activity of key masticatory muscles. METHOD Twenty-two participants were recruited for the study. They were instructed to chew four commercially available gums: group 1 comprised sugar gum with a strong flavor; group 2 included gum containing sorbitol; group 3 consisted of gum containing xylitol; and group 4 provided sugar gum with a mild flavor. Electromyogram (EMG) recordings were utilized to assess muscle activity. Various aspects of muscle activity, including chewing time, maximum muscle potential, and coordination between different muscles, were evaluated. Data tabulation and analysis were performed using IBM SPSS software version 23.0 (IBM Corp., Armonk, NY). RESULT Analysis revealed that in terms of temporalis symmetry, group 2 exhibited the highest mean deviation, while for masseter symmetry, group 3 demonstrated the highest mean deviation. The total deviation for the temporalis and masseter muscles was 72.16% and 65.55%, respectively, indicating greater symmetry in the temporalis muscle. Additionally, group 3 displayed the highest mean deviation in both left and right-sided synergic activity of the muscles. The total deviation for the right and left sides was 64.34% and 65.67%, respectively. CONCLUSION The findings suggest that sugar-free chewing gums elicit increased muscle activity compared to sugar-containing chewing gums. Furthermore, the utilization of calorie-free chewing gums with a firm texture was associated with better-coordinated muscle activity. These results provide valuable insights into the effects of different chewing gums on masticatory muscle function and coordination, which may have implications for therapeutic interventions and oral health management.
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Affiliation(s)
- Keshav Rajesh
- Oral Pathology and Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Sandhya Sundar
- Oral Pathology and Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Vaishnavi Rajaraman
- Prosthodontics and Implantology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
| | - Ramya Ramadoss
- Oral Pathology and Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical sciences, Saveetha University, Chennai, IND
| | - Suresh Venugopalan
- Prosthodontics and Implantology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, IND
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Keller JK, Dulovic A, Gruber J, Griesbaum J, Schneiderhan-Marra N, Wülfing C, Kruse J, Hartmann A, Diekhof EK. SARS-CoV-2 specific sIgA in saliva increases after disease-related video stimulation. Sci Rep 2023; 13:22631. [PMID: 38123577 PMCID: PMC10733377 DOI: 10.1038/s41598-023-47798-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 11/18/2023] [Indexed: 12/23/2023] Open
Abstract
Secretory immunoglobulin A (sIgA) in saliva is the most important immunoglobulin fighting pathogens in the respiratory tract and may thus play a role in preventing SARS-CoV-2 infections. To gain a better understanding of the plasticity in the mucosal antibody, we investigated the proactive change in secretion of salivary SARS-CoV-2-specific sIgA in 45 vaccinated and/or previously infected, generally healthy persons (18 to 35 years, 22 women). Participants were exposed to a disease video displaying humans with several respiratory symptoms typical for COVID-19 in realistic situations of increased contagion risk. The disease video triggered an increase in spike-specific sIgA, which was absent after a similar control video with healthy people. The increase further correlated inversely with revulsion and aversive feelings while watching sick people. In contrast, the receptor binding domain-specific sIgA did not increase after the disease video. This may indicate differential roles of the two salivary antibodies in response to predictors of airborne contagion. The observed plasticity of spike-specific salivary antibody release after visual simulation of enhanced contagion risk suggests a role in immune exclusion.
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Affiliation(s)
- Judith K Keller
- Department of Biology, Neuroendocrinology and Human Biology Unit, Faculty of Mathematics, Informatics and Natural Sciences, Institute for Animal Cell and Systems Biology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.
| | - Alex Dulovic
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Jens Gruber
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Johanna Griesbaum
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | | | - Clemens Wülfing
- Department of Biology, Interdisciplinary Neurobiology and Immunology, Faculty of Mathematics, Informatics and Natural Sciences, Institute for Animal Cell and Systems Biology, Universität Hamburg, Hamburg, Germany
| | - Jana Kruse
- Department of Biology, Neuroendocrinology and Human Biology Unit, Faculty of Mathematics, Informatics and Natural Sciences, Institute for Animal Cell and Systems Biology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Annika Hartmann
- Department of Biology, Neuroendocrinology and Human Biology Unit, Faculty of Mathematics, Informatics and Natural Sciences, Institute for Animal Cell and Systems Biology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
| | - Esther K Diekhof
- Department of Biology, Neuroendocrinology and Human Biology Unit, Faculty of Mathematics, Informatics and Natural Sciences, Institute for Animal Cell and Systems Biology, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany.
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He W, Liang L, Zhang Y. Pungency Perception and the Interaction with Basic Taste Sensations: An Overview. Foods 2023; 12:2317. [PMID: 37372528 DOI: 10.3390/foods12122317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/17/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
The perception of pungency can be attributed to the combination of pain and heat, and it has critical impacts on food flavor and food consumption preferences. Many studies have reported a variety of pungent ingredients with different Scoville heat units (SHU), and the mechanism of pungent perception was revealed in vivo and in vitro. The worldwide use of spices containing pungent ingredients has led to an increasing awareness of their effects on basic tastes. However, the interaction between basic tastes and pungency perception based on structure-activity relationship, taste perception mechanism and neurotransmission lacks review and summary, considering its brighter prospects in food flavor. Thus, in this review, common pungency substances and pungency evaluation methods, and the mechanism of pungency perception is presented, and the interaction between basic tastes and pungency perception and the possible factors of their interaction are reviewed in detail. Pungent stimuli are mainly transduced through transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential fixed hormone isoform (TRPA1) activated by stimulants. Using modern detection techniques combined with sensory standards, different substances produce different degrees of pungent stimulation, ranging from 104 to 107 SHU/g. Pungent stimuli can affect taste receptor or channel protein conformation and regulate taste bud cell sensitivity by producing neurotransmission products. The products of neurotransmission and taste receptor cell activation in turn act on taste perception. When there are simultaneous effects of taste perception, pungency stimulation may enhance the perception of salty at a certain concentration, with a mutual inhibition effect with sour, sweet, and bitter taste, while its interaction with umami taste is not obvious. However, due to the complexity of perception and the uncertainty of many perceptual receptors or channels, the current studies of interactions are still controversial. Based on the understanding of the mechanism and influencing factors, the availability of pungency substances is proposed in the perspective of food industry in order to achieve new development.
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Affiliation(s)
- Wei He
- Food Laboratory of Zhongyuan, Beijing Technology and Business University, Beijing 100048, China
- Key Laboratory of Flavor Science of China General Chamber of Commerce, Beijing Technology and Business University, Beijing 100048, China
| | - Li Liang
- Food Laboratory of Zhongyuan, Beijing Technology and Business University, Beijing 100048, China
- Key Laboratory of Flavor Science of China General Chamber of Commerce, Beijing Technology and Business University, Beijing 100048, China
| | - Yuyu Zhang
- Food Laboratory of Zhongyuan, Beijing Technology and Business University, Beijing 100048, China
- Key Laboratory of Flavor Science of China General Chamber of Commerce, Beijing Technology and Business University, Beijing 100048, China
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Yang HL, Liu FC, Tsay PK, Chou AH, Lin CC, Yu HP, Jao HC, Liu HE. Use of Transcutaneous Electrical Nerve Stimulation to Alleviate Thirst After Surgery: A Randomized Controlled Trial. J Perianesth Nurs 2023; 38:291-296. [PMID: 36464571 DOI: 10.1016/j.jopan.2022.07.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/16/2022] [Accepted: 07/28/2022] [Indexed: 12/04/2022]
Abstract
PURPOSE This prospective study investigated the preventive effect of transcutaneous electrical nerve stimulation (TENS) for postoperative thirst. DESIGN This experimental study was conducted with the CONSORT checklist. METHODS A total of 105 surgical patients who received general anesthesia were recruited from a medical center. Each patient was randomly assigned to the experimental group (n = 53; 20 min of TENS) or the control group (n = 52; routine care). In each group, oral moisture wetness was measured at 1 min, 20 min, and 50 min post-surgery. Descriptive and inferential statistics (Chi-square test, t test, one-way ANOVA, and generalized estimating equation (GEE) regression analysis) were performed to assess the proposed relationships. FINDINGS The two groups showed similar characteristics at baseline. The oral moisture wetness was significantly higher in the experimental group than the control group at each post-surgery assessment time (all P < .001). The GEE results showed that patients in the experimental group reported more oral moisture wetness than patients in the control group. CONCLUSIONS This study demonstrated that TENS can reduce thirst reported by patients after general anesthesia. Thus, this method may have clinical applications for managing postoperative thirst.
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Affiliation(s)
- Hsiu-Ling Yang
- Department of Nursing, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C; School of Nursing, Chang Gung University, Taoyuan, Taiwan, R.O.C
| | - Fu-Chao Liu
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C; College of Medicine, Chang Gung University, Taoyuan, Taiwan, R.O.C
| | - Pei-Kwei Tsay
- College of Medicine, Chang Gung University, Taoyuan, Taiwan, R.O.C
| | - An-Hsun Chou
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C
| | - Chih-Chung Lin
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C
| | - Huang-Ping Yu
- Department of Anesthesiology, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C
| | - Hui-Chuan Jao
- Department of Nursing, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C
| | - Hsueh-Erh Liu
- School of Nursing, Chang Gung University, Taoyuan, Taiwan, R.O.C; Department of Rheumatology, Chang Gung Memorial Hospital, Linkou, Taiwan, R.O.C; Department of Nursing, College of Nursing, Chang Gung University of Science and Technology, Taoyuan, Taiwan, R.O.C.
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Yamada R, Tanaka Y, Sugimoto H, Kodama N, Yoshida R, Minagi S. Effect of continuous sweet gustatory stimulation on salivary flow rate over time. Arch Oral Biol 2023; 146:105590. [PMID: 36463789 DOI: 10.1016/j.archoralbio.2022.105590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/20/2022] [Accepted: 11/24/2022] [Indexed: 12/02/2022]
Abstract
OBJECTIVE This study aimed to determine changes in saliva secretion and subjective taste intensity during a sustained period with continuous gustatory stimulation. DESIGN Twenty-two healthy adults participated in this study. The selected taste solutions were aspartame, sucralose, and acesulfame potassium, which are nonnutritive sweeteners. The concentrations of sucralose1 and acesulfame potassium were set to show the same sweetness intensity as aspartame. Sucralose2 was twice the concentration of sucralose1. The solution was continuously fed into the oral cavity at a flow rate of 0.04 mL / min through a neck-worn precise infusion system. The salivary flow rate (g/min) after 10 min of intraoral water supply from the device was used as the baseline. Salivary flow rate, subjective taste intensity evaluated by the visual analog scale (VAS), and salivary flow rate relative to the baseline were recorded at 10, 30, 60, and 120 min after the start of the test. RESULTS In the aspartame, sucralose1, and sucralose2 groups, the salivary flow rate increased significantly from 10 min to 120 min after the start of the test when compared to the rate at baseline (p < 0.05). The relative salivary flow rate increased and the VAS value decreased significantly over time and were affected by the time factor (p < 0.001, p = 0.013, respectively) but not by the sweetener-group factor and the interaction effects. CONCLUSIONS Continuous gustatory stimulation may maintain increased salivary production for a sustained period.
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Affiliation(s)
- Ranko Yamada
- Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan
| | - Yuki Tanaka
- Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan
| | - Hikaru Sugimoto
- Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan.
| | - Naoki Kodama
- Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan
| | - Ryusuke Yoshida
- Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan
| | - Shogo Minagi
- Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, 700-8525 Okayama, Japan
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Sex differences in estimates of cardiac autonomic function using heart rate variability: effects of dietary capsaicin. Eur J Appl Physiol 2023; 123:1041-1050. [PMID: 36633663 DOI: 10.1007/s00421-023-05136-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 01/07/2023] [Indexed: 01/13/2023]
Abstract
PURPOSE Heart rate variability (HRV) estimates the autonomic nervous system (ANS) influence on the heart and appears sex-specific. Sensory afferents exhibit sex-specificity; although, it is unknown if Capsaicin, an agonist for transient receptor potential vanilloid channel-1 (TRPV1), alters cardiac ANS activity in a sex-dependent manner, which could be important given the predictive nature of HRV on risk of developing hypertension. Thus, we explored if there was sex-specificity in the effect of capsaicin on estimated cardiac ANS activity. METHODS HRV was measured in 38 young males (M: n = 25) and females (F: n = 13), in a blinded-crossover design, after acute ingestion of placebo or capsaicin. Resting HR, RR-interval, root-mean-square of successive differences (RMSSD), natural log-transformed RMSSD (LnRMSSD), standard deviation of n-n intervals (SDNN), number of pairs of successive n-n intervals differing by > 50 ms (NN50), and percent NN50 (PNN50) were obtained using standard techniques. RESULTS Significant sex differences were observed in mean HR (M: 59 ± 9.3 vs. F: 65 ± 12 beats/min, p = 0.036, η2 = 0.098), minimum HR (M: 47 ± 8.3 vs. F: 56 ± 12 beats/min, p = 0.014, η2 = 0.124), and NN50 (M: 177 ± 143 vs. F: 29 ± 17, p < 0.001, η2 = 0.249). There was a significant interaction of sex*treatment (p = 0.02, η2 = 0.027) for RMSSD, where males increased (78 ± 55 vs. 91 ± 64 ms), and females decreased (105 ± 83 vs. 76 ± 43 ms), placebo vs. capsaicin. CONCLUSION This controlled study recapitulates sex differences in HR and HRV, but revealed a sexual dimorphism in the parasympathetic response to capsaicin, perhaps due to differing TRPV1-afferent sensitivity, highlighting a potential mechanism for differential regulation of hemodynamics, and CVD risk, and should be considered in future studies.
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Shang YF, Shen YY, Zhang MC, Lv MC, Wang TY, Chen XQ, Lin J. Progress in salivary glands: Endocrine glands with immune functions. Front Endocrinol (Lausanne) 2023; 14:1061235. [PMID: 36817607 PMCID: PMC9935576 DOI: 10.3389/fendo.2023.1061235] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/09/2023] [Indexed: 02/05/2023] Open
Abstract
The production and secretion of saliva is an essential function of the salivary glands. Saliva is a complicated liquid with different functions, including moistening, digestion, mineralization, lubrication, and mucosal protection. This review focuses on the mechanism and neural regulation of salivary secretion, and saliva is secreted in response to various stimuli, including odor, taste, vision, and mastication. The chemical and physical properties of saliva change dynamically during physiological and pathophysiological processes. Moreover, the central nervous system modulates salivary secretion and function via various neurotransmitters and neuroreceptors. Smell, vision, and taste have been investigated for the connection between salivation and brain function. The immune and endocrine functions of the salivary glands have been explored recently. Salivary glands play an essential role in innate and adaptive immunity and protection. Various immune cells such as B cells, T cells, macrophages, and dendritic cells, as well as immunoglobins like IgA and IgG have been found in salivary glands. Evidence supports the synthesis of corticosterone, testosterone, and melatonin in salivary glands. Saliva contains many potential biomarkers derived from epithelial cells, gingival crevicular fluid, and serum. High level of matrix metalloproteinases and cytokines are potential markers for oral carcinoma, infectious disease in the oral cavity, and systemic disease. Further research is required to monitor and predict potential salivary biomarkers for health and disease in clinical practice and precision medicine.
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Affiliation(s)
- Yu Feng Shang
- Department of Stomatology, Key Laboratory of Oral Biomedical Research of Zhejiang Province, The First Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang University School of Stomatology, Hangzhou, China
| | - Yi Yang Shen
- Department of Stomatology, Key Laboratory of Oral Biomedical Research of Zhejiang Province, The First Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang University School of Stomatology, Hangzhou, China
| | - Meng Chen Zhang
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
| | - Min Chao Lv
- Department of Orthopedics, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Quzhou, China
| | - Tong Ying Wang
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, School of Brain Science and Brain Medicine, Hangzhou, China
| | - Xue Qun Chen
- National Health Commission and Chinese Academy of Medical Sciences Key Laboratory of Medical Neurobiology, MOE Frontier Science Center for Brain Research and Brain Machine Integration, School of Brain Science and Brain Medicine, Zhejiang University, Hangzhou, China
- Department of Neurobiology, Department of Neurology of the Second Affiliated Hospital, School of Brain Science and Brain Medicine, Hangzhou, China
| | - Jun Lin
- Department of Stomatology, Key Laboratory of Oral Biomedical Research of Zhejiang Province, The First Affiliated Hospital, School of Medicine, Zhejiang University, Zhejiang University School of Stomatology, Hangzhou, China
- *Correspondence: Jun Lin,
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Does sex influence near-infrared spectroscopy-derived indicators of microvascular reactivity and the response to acute dietary capsaicin. Microvasc Res 2023; 145:104436. [PMID: 36113667 DOI: 10.1016/j.mvr.2022.104436] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/28/2022] [Accepted: 09/10/2022] [Indexed: 02/03/2023]
Abstract
Endothelial dysfunction is associated with cardiovascular disease development, nitric oxide (NO) deficiencies, and may be limb or sex-specific. Prior in vitro work indicated that the transient receptor potential vanilloid channel-1 (TRPV1) is expressed in human arteries and the TRPV1 agonist capsaicin alters vasodilation in an endothelium-dependent manner; however, it is unknown if this translates in vivo or is limb or sex-dependent. Therefore, we sought to determine if there was limb or sex-specificity in the effect of capsaicin on microvascular function using near-infrared spectroscopy (NIRS)-derived tissue oxygen saturation (StO2) reperfusion slope. In a blinded placebo-controlled crossover design, 45 young males (M: n = 25) and females (F: n = 20), the reperfusion slopes of the forearm and quadriceps were assessed, and a urine sample obtained to assay for nitrate/nitrite (NOx) concentrations and antioxidant capacity after acutely ingesting placebo or capsaicin. Under placebo, females had greater reperfusion rates in both the forearm (M: 0.44 ± 0.24 vs. F: 0.98 ± 0.46 %/sec; p = 0.002, d = -1.50) and quadricep (M: 0.86 ± 0.31 vs. F: 1.17 ± 0.43 %/sec; p = 0.010, d = -0.85). Capsaicin decreased microvascular responsiveness in the forearm of females (placebo: 0.98 ± 0.45 vs. capsaicin: 0.84 ± 0.45 %/sec) as compared to males (placebo: 0.45 ± 0.24 vs. capsaicin: 0.38 ± 0.16 %/sec, interaction p < 0.001, η2 = 0.475). There was a sex*treatment interaction for NOx concentrations, where males increased (placebo: 21.13 ± 12.83 vs. capsaicin: 23.82 ± 13.34 μM), while females decreased (placebo: 22.78 ± 14.40 vs. capsaicin: 14.43 ± 10.01 μM; p = 0.037, η2 = 0.042). Using NIRS to assess microvascular function, there is apparent limb and sex-specificity, and, for the first-time, document that acute oral capsaicin alters reperfusion slope in a sexually divergent manner.
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Keller JK, Wülfing C, Wahl J, Diekhof EK. Disease-related disgust promotes antibody release in human saliva. Brain Behav Immun Health 2022; 24:100489. [PMID: 35866104 PMCID: PMC9293731 DOI: 10.1016/j.bbih.2022.100489] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 07/07/2022] [Accepted: 07/08/2022] [Indexed: 11/25/2022] Open
Abstract
The behavioral immune system (BIS) comprises manifold mechanisms, that may assist the physiological immune system (PIS) in counteracting infection and can even reduce the risk of contagion. Previous studies have found initial evidence for possible interactions between the two systems. However, most of these findings were correlative and have not been replicated. Further, none of these studies examined whether disease stimuli that indicate an enhanced airborne transmission risk may trigger a different immune response in comparison to stimuli that predominantly evoke core disgust. In the present study, we employed a video-priming approach to get further insight in the influence of the perception of disgust- and disease-related stimuli on the rapid physiological immune response, as indicated by changes of secretory immunoglobulin A (S-IgA) in saliva. We created three video primers that represented different categories of disgust- and/or disease-associated content. Two of the videos showed disease-related situations that were associated with contagious respiratory virus infections, varying in concealment of aerosols. The third video incurred no heightened airborne contagion risk, but comprised situations that are known to elicit core disgust, such as rotten foods, decaying animal carcasses, or cockroaches. A fourth video acted as control showing landscape impressions. The different video primers varied in their contagion risk and disgust-evoking potential. Given the role of S-IgA in the mucosal immune defense, we expected differences in the S-IgA response between the two videos indicating a heightened airborne contagion risk and the core disgust video, with the highest S-IgA to occur after the aerosol video. For this, we used the data of 107 healthy participants in a between-subjects design with the four video primers. We found a significant increase of S-IgA in response to both the disease- and the disgust-related videos, which correlated positively with the perceived contagion risk of the displayed situations. Nevertheless, there was no significant difference in the increase between the three disease- and disgust-related videos. We also found that people with a high contamination disgust produced less S-IgA in such situations, which is a hint for a compensating relationship between the BIS and PIS. Our observations suggest that the mere visual perception of videos showing realistic situations of an increased contagion risk can elicit a heightened release of salivary antibodies. Realistic videos of respiratory diseases are efficient to trigger immune responses. Secretory Immunoglobulin A (S-IgA) in saliva increases after video-priming. S-IgA increase is positively correlated with perceived contagion risk. S-IgA increase is inversely correlated with the trait contamination disgust.
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Effect of an Extremely Low-Frequency Electromagnetic Field on the Concentration of Salivary Immunoglobulin A. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19105786. [PMID: 35627323 PMCID: PMC9141657 DOI: 10.3390/ijerph19105786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 02/01/2023]
Abstract
Extremely Low-Frequency Electromagnetic Field (ELF MF) therapy is effective in the treatment of injury, inflammation and postoperative complications. Its clinical applications relate to bone unification, pain reduction, soft tissue oedema and the decrease of electric potentials in the oral cavity. It enhances regeneration of periapical bone lesions. It is obvious that cells (leukocytes, platelets, keratinocytes, osteoblasts) and proteins (fibrin, collagen, elastin and growth factors) exhibit alterations when exposed to an Extremely Low-Frequency Electromagnetic Field. The aim of the study was to evaluate the effect of an Extremely Low-Frequency Electromagnetic Field (ELF MF) on the parotid gland on the concentration of salivary immunoglobulin A. The study group consisted of 24 patients, aged 14–16, who underwent ELF MF on the parotid gland region. The control group comprised 25 matching persons. The IgA concentration in saliva samples was established using radial immunodiffusion. Following ELF MF, a statistically significant increase in the concentration of secretory immunoglobulin A was found in the study group, whereas in the control group, no statistically significant differences were noted. It can be concluded that an Extremely Low-Frequency Electromagnetic Field increases the activity of the immune system of the parotid gland.
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Sekiya T, Sugimoto K, Kubota A, Tsuchihashi N, Oishi A, Yoshida N. Assessment of psychological changes in young children during dental treatment: Analysis of the autonomic nervous activity and electroencephalogram. Int J Paediatr Dent 2022; 32:418-427. [PMID: 34558749 DOI: 10.1111/ipd.12921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/12/2021] [Accepted: 09/11/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND Understanding the emotional changes in children during dental treatment is necessary for providing stress-free care. AIM To objectively assess the stress associated with dental treatment in children, based on the autonomic nervous activity and the electroencephalogram (EEG). DESIGN Twenty-two children aged 4-9 years were recruited from outpatients of a paediatric clinic. Electrocardiogram and EEG were recorded throughout the treatment to analyze the autonomic nervous activities and the powers of brain waves, respectively. Changes in these measurements during each treatment process were evaluated in two age groups: 4-6 years and 6-9 years. RESULTS Elevations in sympathetic activities accompanied by decreased parasympathetic activities induced by stress were observed during rubber dam setting (RD) in the age group of 4-6 years and during infiltration anesthesia (IA), RD, and cavity preparation with a dental turbine (CP-T) in the age group of 6-9 years. Stress-related beta wave increments in EEG were observed during IA and CP-T in the age group of 6-9 years but not in the age group of 4-6 years. CONCLUSION Monitoring the autonomic nervous activities during treatments is useful in assessing stresses in a wide age of young children, whereas EEG monitoring is applicable only to children older than 6 years.
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Affiliation(s)
- Taki Sekiya
- Department of Paediatric Dentistry/Special Needs Dentistry, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kumiko Sugimoto
- Department of Oral Health Care Education, Health Sciences and Biomedical Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ayako Kubota
- Department of Oral Health Care Education, Health Sciences and Biomedical Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Natsumi Tsuchihashi
- Department of Paediatric Dentistry/Special Needs Dentistry, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Atsushi Oishi
- Department of Paediatric Dentistry/Special Needs Dentistry, Division of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Naomi Yoshida
- Department of Oral Health Care Education, Health Sciences and Biomedical Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
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12
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Essential Oils, Phytoncides, Aromachology, and Aromatherapy—A Review. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12094495] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Chemical compounds from plants have been used as a medicinal source for various diseases. Aromachology is a unique field that studies the olfactory effects after inhaling aromatic compounds. Aromatherapy is a complementary treatment methodology involving the use of essential oils containing phytoncides and other volatile organic compounds for various physical and mental illnesses. Phytoncides possess an inherent medicinal property. Their health benefits range from treating stress, immunosuppression, blood pressure, respiratory diseases, anxiety, and pain to anti-microbial, anti-larvicidal, anti-septic, anti-cancer effects, etc. Recent advancements in aromatherapy include forest bathing or forest therapy. The inhalation of phytoncide-rich forest air has been proven to reduce stress-induced immunosuppression, normalize immune function and neuroendocrine hormone levels, and, thus, restore physiological and psychological health. The intricate mechanisms related to how aroma converts into olfactory signals and how the olfactory signals relieve physical and mental illness still pose enormous questions and are the subject of ongoing research. Aromatherapy using the aroma of essential oils/phytoncides could be more innovative and attractive to patients. Moreover, with fewer side effects, this field might be recognized as a new field of complementary medicine in alleviating some forms of physical and mental distress. Essential oils are important assets in aromatherapy, cosmetics, and food preservatives. The use of essential oils as an aromatherapeutic agent is widespread. Detailed reports on the effects of EOs in aromatherapy and their pharmacological effects are required to uncover its complete biological mechanism. This review is about the evolution of research related to phytoncides containing EOs in treating various ailments and provides comprehensive details from complementary medicine.
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Castillo-Lopez E, Rivera-Chacon R, Ricci S, Petri RM, Reisinger N, Zebeli Q. Short-term screening of multiple phytogenic compounds for their potential to modulate chewing behavior, ruminal fermentation profile, and pH in cattle fed grain-rich diets. J Dairy Sci 2021; 104:4271-4289. [PMID: 33612222 DOI: 10.3168/jds.2020-19521] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/05/2020] [Indexed: 12/15/2022]
Abstract
In cattle, proper rumen functioning and digestion are intimately linked to chewing behavior. Yet, high grain feeding impairs chewing activity, increasing the risk of subacute ruminal acidosis and dysfermentation. This study aimed to screen 9 different phytogenic compounds for their potential to modulate chewing activity, meal size, rumino-reticular short-chain fatty acids (SCFA), and pH during consumption in a first daily meal and shortly thereafter in cattle fed a grain-rich diet. Treatments were control (total mixed ration without phytogenic) or addition of a phytogenic compound at a low or high dose. Phytogenic compounds and doses (all in mg/kg) were angelica root (6.6 and 66), capsaicin (10 and 100), gentian root (6.6 and 66), garlic oil (0.3 and 3), ginger extract (40 and 400), L-menthol (6.7 and 67), mint oil (15.3 and 153), thyme oil (9.4 and 94), and thymol (5 and 50), for the low and high groups, respectively. Before the start of the screening experiment, cows were fed to reach subacute ruminal acidosis conditions, confirmed with the time of ruminal pH <5.8 being 655 ± 148.2 min/d. During the screening experiment, the treatments were offered in a controlled meal (2.5 kg of DM for 4 h) as part of the daily diet with 65% concentrate. Each treatment was tested in 4 of the 9 cannulated Holstein cows using an incomplete Latin square design. Ruminal and reticular fluids were sampled before and after each treatment, and data collected before the meal were used as covariates. Chewing and ruminal pH were monitored during the treatment, followed by 2 h of complete feed restriction, and then 4 h of ad libitum feed intake without phytogenic. Data showed that supplementation of angelica root tended to linearly increase rumination time immediately after the first meal when feed was restricted (27.3, 41.9, and 42.6 ± 5.99 min for control, low and high groups, respectively). Capsaicin increased eating time (43.6, 49.4, and 66.4 ± 4.93 min) during consumption but did not affect ruminal total SCFA or mean ruminal pH. Garlic oil reduced the concentration of reticular total SCFA (75.7, 71.3, and 60.1 mM) and tended to decrease ruminal acetate-to-propionate ratio (2.50, 1.78, and 1.87 ± 0.177) with no effect on ruminal pH. The L-menthol affected reticular total SCFA quadratically (76.1, 64.9, and 81.0 ± 4.22%), and ruminal pH responded quadratically when feed was reintroduced ad libitum (6.0, 6.3, and 6.1 ± 0.07). Mint oil did not affect chewing or total SCFA during consumption, but the low dose increased ruminal pH (6.5, 6.7, and 6.5 ± 0.08). Thyme oil tended to lower the severity of ruminal acidosis. Overall, phytogenic compounds demonstrated distinct dose-dependent effects to beneficially influence chewing behavior, modulate fermentation, and mitigate ruminal acidosis in dairy cows under a high-grain challenge diet.
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Affiliation(s)
- Ezequias Castillo-Lopez
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Christian Doppler Laboratory for Innovative Gut Health Concepts of Livestock, Veterinärplatz 1, 1210 Vienna, Austria
| | - Raul Rivera-Chacon
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Christian Doppler Laboratory for Innovative Gut Health Concepts of Livestock, Veterinärplatz 1, 1210 Vienna, Austria
| | - Sara Ricci
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Christian Doppler Laboratory for Innovative Gut Health Concepts of Livestock, Veterinärplatz 1, 1210 Vienna, Austria
| | - Renee M Petri
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Christian Doppler Laboratory for Innovative Gut Health Concepts of Livestock, Veterinärplatz 1, 1210 Vienna, Austria
| | - N Reisinger
- BIOMIN Research Center, BIOMIN Holding GmbH, 3430 Tulln, Austria
| | - Q Zebeli
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria; Christian Doppler Laboratory for Innovative Gut Health Concepts of Livestock, Veterinärplatz 1, 1210 Vienna, Austria.
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Subjective Effects of Inhaling Kuromoji Tea Aroma. Molecules 2021; 26:molecules26030575. [PMID: 33499197 PMCID: PMC7866097 DOI: 10.3390/molecules26030575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/31/2020] [Accepted: 01/18/2021] [Indexed: 11/17/2022] Open
Abstract
Teas and various herbal teas are well-known beverages and are commonly consumed around the world. In this study, we focused on kuromoji tea. Kuromoji is a deciduous shrub of the Lauraceae family, and the plucked leaves and branches have been drunk as a tea in production areas for a long time. However, no studies have investigated the subjective and physiological effects of kuromoji tea. In this study, the effects of kuromoji tea were examined on the basis of the measurements of heart rate variability and cerebral blood flow, core body temperature and subjective assessments. Moreover, the results of this study showed that a pleasant subjective feeling could be obtained by sniffing the aroma of kuromoji teas, especially tea leaves. It was also found that the aroma of kuromoji teas has the potential to stimulate saliva secretion and increase subjective and physiological excitements in the oral cavity. 1,8-Cineole, linalool, terpinen-4-ol, carvone and geraniol were determined in both kuromoji leaves and branches. In this study, the beneficial effects of kuromoji teas when drunk conventionally were investigated.
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Houghton JW, Carpenter G, Hans J, Pesaro M, Lynham S, Proctor G. Agonists of Orally Expressed TRP Channels Stimulate Salivary Secretion and Modify the Salivary Proteome. Mol Cell Proteomics 2020; 19:1664-1676. [PMID: 32651226 PMCID: PMC8014997 DOI: 10.1074/mcp.ra120.002174] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Indexed: 11/06/2022] Open
Abstract
Natural compounds that can stimulate salivary secretion are of interest in developing treatments for xerostomia, the perception of a dry mouth, that affects between 10 and 30% of the adult and elderly population. Chemesthetic transient receptor potential (TRP) channels are expressed in the surface of the oral mucosa. The TRPV1 agonists capsaicin and piperine have been shown to increase salivary flow when introduced into the oral cavity but the sialogogic properties of other TRP channel agonists have not been investigated. In this study we have determined the influence of different TRP channel agonists on the flow and protein composition of saliva. Mouth rinsing with the TRPV1 agonist nonivamide or menthol, a TRPM8 agonist, increased whole mouth saliva (WMS) flow and total protein secretion compared with unstimulated saliva, the vehicle control mouth rinse or cinnamaldehyde, a TRPA1 agonist. Nonivamide also increased the flow of labial minor gland saliva but parotid saliva flow rate was not increased. The influence of TRP channel agonists on the composition and function of the salivary proteome was investigated using a multi-batch quantitative MS method novel to salivary proteomics. Inter-personal and inter-mouth rinse variation was observed in the secreted proteomes and, using a novel bioinformatics method, inter-day variation was identified with some of the mouth rinses. Significant changes in specific salivary proteins were identified after all mouth rinses. In the case of nonivamide, these changes were attributed to functional shifts in the WMS secreted, primarily the over representation of salivary and nonsalivary cystatins which was confirmed by immunoassay. This study provides new evidence of the impact of TRP channel agonists on the salivary proteome and the stimulation of salivary secretion by a TRPM8 channel agonist, which suggests that TRP channel agonists are potential candidates for developing treatments for sufferers of xerostomia.
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Affiliation(s)
- Jack William Houghton
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK; Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, UK.
| | - Guy Carpenter
- Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, UK
| | | | | | - Steven Lynham
- Proteomics Facility, King's College London, London, UK
| | - Gordon Proctor
- Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, UK
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16
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Morita K, Kimura H, Tsuka H, Nishio F, Yoshida M, Tsuga K. Association between salivary alpha-amylase and subjective and objective oral parafunctions in community-dwelling elderly individuals. J Dent Sci 2020; 15:310-314. [PMID: 32952889 PMCID: PMC7486515 DOI: 10.1016/j.jds.2020.05.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 05/03/2020] [Indexed: 12/19/2022] Open
Abstract
Background/purpose Stress in the elderly is caused by loss of physical and psychological health. Although there have been many reports on the intraoral environment affecting physical health, few reports exist on stress and the intraoral environment in the elderly. The aim of this study was to investigate the relationship between salivary α-amylase as an index of stress value and the intraoral environment. Materials and methods Three hundred and nineteen participants were community-dwelling independent individuals over 65 years old. The outcome variable was salivary α-amylase. After measurement, salivary α-amylase was classified into four groups (0 = 0–30, 1 = 31–45, 2 = 46–60, 3 = 61–200). The predictor variables were physical status (which includes age and male body-mass index) and subjective and objective symptoms (which include present teeth, torus palatinus, torus mandibularis, temporomandibular joint noise, bruxism, and dental attrition). These variables were compared among participants using univariate analysis and multiple logistic regression analysis. Results The participants included 77 men and 242 women, with a mean age of 75.8 ± 5.4 years (65–94 years). Although temporomandibular joint noise and dental attrition were significantly positively correlated with salivary α-amylase, bruxism was significantly negatively correlated with salivary α-amylase (p < 0.05). Stepwise regression analysis revealed a significant relationship between salivary α-amylase and temporomandibular joint noise, bruxism, and dental attrition. Conclusion High salivary α-amylase is associated with a high rate of temporomandibular joint noise and dental attrition, and a low rate of bruxism among elderly participants.
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Affiliation(s)
- Koji Morita
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Hitomi Kimura
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Hiroki Tsuka
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Fumiko Nishio
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Mitsuyoshi Yoshida
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Kazuhiro Tsuga
- Department of Advanced Prosthodontics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
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Gardner A, So P, Carpenter G. Endogenous salivary citrate is associated with enhanced rheological properties following oral capsaicin stimulation. Exp Physiol 2020; 105:96-107. [PMID: 31705555 PMCID: PMC6973168 DOI: 10.1113/ep088166] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 11/04/2019] [Indexed: 12/14/2022]
Abstract
NEW FINDINGS What is the central question of this study? What are the relationships between physical properties of saliva, protein composition and metabolite composition? What is the main finding and its importance? Salivary citrate, one of the major endogenous metabolites in saliva, increased upon capsaicin stimulation and was associated with improved physical properties measured by extensional rheology. This suggests salivary gland citrate transporters might be a valuable area of future study. ABSTRACT Saliva displays viscoelastic properties which enable coating, lubrication and protection of the oral mucosa and hard tissues. Individuals lacking saliva or perceiving oral dryness can manage their symptoms using artificial saliva preparations, but these often fail to mimic the sensation and functionality of natural saliva. It is widely acknowledged that mucins (MUC7 and MUC5B) confer saliva's rheological properties, but artificial saliva containing purified mucins is still often an inadequate substitute. This work aimed to explore salivary components that influence salivary extensional rheology to better understand how natural saliva could be replicated. Saliva was stimulated via control and capsaicin solutions in healthy volunteers. Extensional rheology was analysed using a CaBER-1 (capillary breakup) extensional rheometer. Protein composition, including mucins, was measured by gel-electrophoresis band densitometry and metabolites were measured by 1 H nuclear magnetic resonance spectroscopy. Capsaicin stimulation significantly increased capillary breakup time, extensional viscosity and the abundance of most major salivary proteins. Stimulation also increased salivary citrate and choline concentrations. Significant correlations were found between capillary breakup time and amylase (r = 0.67, P < 0.05), statherin (ρ = 0.66, P < 0.05) and citrate (ρ = 0.81, P < 0.01). The relationship between citrate and salivary rheology was subsequently investigated in vitro. These results suggest that citrate and non-mucin proteins are stronger predictors of salivary rheology than the more often studied mucin glycoproteins. Potential mechanisms are discussed and future work in this area could help formulate more effective saliva substitutes, more closely resembling natural saliva.
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Affiliation(s)
- Alexander Gardner
- Salivary Research, Centre for Host‐Microbiome InteractionsFaculty of Dental, Oral & Craniofacial SciencesKing's College LondonLondonUK
- Department of Restorative Dentistry, Dental Hospital and SchoolUniversity of DundeeDundeeUK
| | - Po‐Wah So
- Department of Neuroimaging, Institute of PsychiatryPsychology and Neuroscience, King's College LondonMaurice Wohl Clinical Neuroscience InstituteLondonUK
| | - Guy Carpenter
- Salivary Research, Centre for Host‐Microbiome InteractionsFaculty of Dental, Oral & Craniofacial SciencesKing's College LondonLondonUK
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