1
|
Eldomiaty MA, A Hassan Z, Halawa AM, Elnajar AM, Almohamadi N. Structural changes and neurotrophic factors upregulation in submandibular gland in a rat model of depression: proposed correlation with stress indicators during and after the relief of depression. Anat Sci Int 2023; 98:185-195. [PMID: 36181656 DOI: 10.1007/s12565-022-00686-3] [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: 03/21/2022] [Accepted: 09/17/2022] [Indexed: 02/07/2023]
Abstract
This study evaluated the structural changes, the immunohistochemical and gene expression of neurotrophic factors in submandibular gland in a rat model of depression, and their correlation with depression parameters during and after relief of depression by voluntary running. Forty-eight male Wistar rats were divided into control, control-exercise, depression, and depression-exercise groups. Depression was induced using forced swimming protocol, while the relief of depression was induced using the rat voluntary running wheels. The depressive state of rats was evaluated by measuring the immobility duration and the serum corticosterone level. The immune expression was evaluated by measuring the optical densities (ODs) using ImageJ software, and the gene expression levels were investigated. In the depression group, the convoluted ducts appeared dilated with numerous secretory granules. The number of PCNA-stained cells was significantly decreased in the depression group as compared to control group and then significantly increased in the depression-exercise group when compared to the depression group with a negative correlation to stress indicator. The ODs of immuno-expression for the brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) increased significantly in the depression group as compared to control group. Both BDNF and VEGF immuno-expression displayed positive correlation with the stress indicators. Both BDNF and VEGF gene expression results confirmed their immunohistochemical results. The findings of this study explored the role of submandibular gland in secreting neurotrophic factors and raise a flag for the possibility of using salivary secretions as dependable and easy parameter for estimation of chronic stressed patients.Mini AbstractThe submandibular gland neurotrophic factors immuno-expression can be used in estimating chronic depressive disorders as they are correlated with stress indicators during and after the relief of depression.
Collapse
Affiliation(s)
- Magda A Eldomiaty
- Department of Anatomy and Histology, Faculty of Medicine, Al-Rayan Medical Colleges, Medina, Saudi Arabia.
- Department of Anatomy, Faculty of Medicine, Tanta University, Tanta, Egypt.
| | - Zeinab A Hassan
- Department of Anatomy, Faculty of Medicine, Taibah University, Medina, Saudi Arabia
- Faculty of Medicine, Histology and Cell Biology, Zagazig University, Zagazig, Egypt
| | - Amal M Halawa
- Department of Anatomy, Faculty of Medicine, Tanta University, Tanta, Egypt
| | | | - Nawal Almohamadi
- Department of Pathology, Faculty of Medicine, Taibah University, Medina, Saudi Arabia
| |
Collapse
|
2
|
Dos Santos HT, Maslow F, Nam K, Trump B, Weisman GA, Baker OJ. A combination treatment of low-dose dexamethasone and aspirin-triggered resolvin D1 reduces Sjögren syndrome-like features in a mouse model. JADA FOUNDATIONAL SCIENCE 2022; 2:100016. [PMID: 37622089 PMCID: PMC10448398 DOI: 10.1016/j.jfscie.2022.100016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
Background Sjögren syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration and diminished secretory function of the salivary glands. Dexamethasone (DEX) resolves dry mouth and lymphocytic infiltration; however, this treatment is difficult to maintain because of multiple adverse effects (eg, osteoporosis and skin thinning); likewise, aspirin-triggered resolvin D1 (AT-RvD1) increases saliva secretion but cannot eliminate lymphocytic infiltration. Previous studies showed that a combination of low-dose DEX with AT-RvD1 before disease onset prevents SS-like features in a mouse model; however, this is not clinically practical because there are no reliable indicators of SS before disease onset. Therefore, the authors applied the combined treatment at disease onset to show its efficacy and comparative lack of adverse effects, so that it may reasonably be maintained over a patient's lifetime. Methods NOD/ShiLtJ mice were treated with ethanol (vehicle control), high-dose DEX alone, AT-RvD1 alone, or a combination of low-dose DEX with AT-RvD1 at disease onset for 8 weeks. Then saliva flow rates were measured, and submandibular glands were harvested for histologic analyses. Results A combined treatment of low-dose DEX with AT-RvD1 significantly decreased mast cell degranulation and lymphocytic infiltration, increased saliva secretion, and restored apical aquaporin-5 expression in submandibular glands of NOD/ShiLtJ mice. Conclusions Low-dose DEX combined with AT-RvD1 reduces the severity of SS-like manifestation and prevents the development of advanced and potentially irreversible damage, all in a form that can reasonably be administered indefinitely without the need to cease treatment because of secondary effects.
Collapse
Affiliation(s)
- Harim Tavares Dos Santos
- Department of Otolaryngology, Head and Neck Surgery, University of Missouri, Columbia, MO
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO
| | - Frank Maslow
- Department of Otolaryngology, Head and Neck Surgery, University of Missouri, Columbia, MO
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO
| | - Kihoon Nam
- Department of Otolaryngology, Head and Neck Surgery, University of Missouri, Columbia, MO
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO
| | - Bryan Trump
- School of Dentistry and Department of Dermatology, University of Utah, Salt Lake City, UT
| | - Gary A Weisman
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO
- Department of Biochemistry, University of Missouri, Columbia, MO
| | - Olga J Baker
- Department of Otolaryngology, Head and Neck Surgery, University of Missouri, Columbia, MO
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO
- Department of Biochemistry, University of Missouri, Columbia, MO
| |
Collapse
|
3
|
Shittu STT, Lasisi TJ, Shittu SAS, Adeyemi A, Adeoye TJ, Alada AA. Ocimum gratissimum enhances insulin sensitivity in male Wistar rats with dexamethasone-induced insulin resistance. J Diabetes Metab Disord 2021; 20:1257-1267. [PMID: 34900777 DOI: 10.1007/s40200-021-00850-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 07/03/2021] [Indexed: 12/12/2022]
Abstract
Purpose The antidiabetic activities of Ocimum gratissimum (OG) leaf extract are well documented in experimental diabetes induced by beta cell destruction resulting in hypoinsulinemia. There is however paucity of data on its effect in conditions characterized by hyperinsulinemia. This study therefore investigated the effect of OG on insulin resistance induced by dexamethasone in male Wistar rats. Method Twenty male Wistar rats grouped as control, normal + OG, Dex and Dex + OG were used. Control and normal + OG received normal saline while Dex and Dex + OG received dexamethasone (1 mg/kg, i.p) followed by distilled water or OG (400 mg/kg) for 10 days. Levels of fasting blood glucose (FBG), insulin, HOMA-IR, liver and muscle glycogen, hexokinase activities, hepatic HMG CoA reductase activity were obtained. Histopathology of pancreas and liver tissues was carried out using standard procedures. Results Body weight reduced significantly in the Dex and Dex + OG groups compared with the control. FBG (147.8 ± 9.93 mg/dL), insulin (2.98 ± 0.49 µIU/ml) and HOMA-IR (1.11 ± 0.22) of Dex animals were higher than the control (FBG = 89.22 ± 6.53 mg/dL; insulin = 1.70 ± 0.49 µIU/ml; HOMA-IR = 0.37 ± 0.04). These were significantly reduced in the Dex + OG (FBG = 115.31 ± 5.93 mg/dL; insulin = 1.85 ± 0.11µIU/ml; HOMA-IR = 0.53 ± 0.08) compared with Dex. Glycogen content and hexokinase activities were increased in the Dex + OG. Increased pancreatic islet size, hepatic steatosis and HMG Co A reductase activity were observed in the Dex but reduced in Dex + OG. Conclusion OG promotes cellular glucose utilization and reduces hepatic fat accumulation in Wistar rats with insulin resistance induced by dexamethasone. Further study to identify the involved signal transduction will throw more light on the observed effects.
Collapse
Affiliation(s)
| | - Taye Jemilat Lasisi
- Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | | | - Adeyinka Adeyemi
- Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Tolulope James Adeoye
- Department of Physiology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | | |
Collapse
|
4
|
Cano IP, Dionisio TJ, Cestari TM, Calvo AM, Colombini-Ishikiriama BL, Faria FAC, Siqueira WL, Santos CF. Losartan and isoproterenol promote alterations in the local renin-angiotensin system of rat salivary glands. PLoS One 2019; 14:e0217030. [PMID: 31116771 PMCID: PMC6530859 DOI: 10.1371/journal.pone.0217030] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 05/02/2019] [Indexed: 12/18/2022] Open
Abstract
Renin-angiotensin system (RAS) systemically or locally collaborates with tissue homeostasis, growth and development, which has been extensively studied for its pharmacological implications. This study was primarily aimed at finding and characterizing local RAS in rat parotid, sublingual and submandibular glands. It was also hypothesized that vasoactive drugs could affect the expression of RAS targets, as well as saliva flow and its composition. Therefore, another objective of this study was to compare the effects of losartan (angiotensin II receptor blocker) and isoproterenol (β-adrenergic receptor agonist). Forty-one Wistar rats were divided into three groups and administered a daily intraperitoneal dose of saline, losartan or isoproterenol solutions for one week. The following RAS targets were studied using qPCR: renin (REN), angiotensinogen (AGT), angiotensin converting enzyme (ACE), ACE-2, elastase-2 (ELA-2), AT1-a and MAS receptors, using RPL-13 as a reference gene. Morphology of glands was analyzed by immunohistochemistry using REN, ACE, ACE-2, AT1, AT2 and MAS antibodies. The volume and total protein content of saliva were measured. Our results revealed that ACE, ACE-2, AT1-a, AT2 and MAS receptors were expressed in all salivary gland samples, but REN and ELA-2 were absent. Losartan decreased mRNA expression of RAS targets in parotid (MAS) and submandibular glands (ACE and both AT receptors), without affecting morphological alterations, and significantly decreased saliva and total protein secretions. Isoproterenol treatment affected gene expression profiles in parotid (ACE, ACE-2, AT1-a, MAS, AGT), and submandibular (ACE, AT2, AGT) glands, thus promoting acinar hypertrophy in serous acini, without significant changes in salivary flow or total protein content. These drugs affected mainly acini, followed by duct systems and myoepithelial cells, whereas blood vessels were not affected. In conclusion, there is a local RAS in major rat salivary glands and losartan, an angiotensin II receptor blocker, affected not only the RAS-target gene expression but also decreased salivary flow and total protein content.
Collapse
Affiliation(s)
- Isadora Prado Cano
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Thiago José Dionisio
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Tânia Mary Cestari
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Adriana Maria Calvo
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | | | - Flávio Augusto Cardoso Faria
- Department of Biochemistry and School of Dentistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Canada
| | - Walter Luiz Siqueira
- Department of Biochemistry and School of Dentistry, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Canada
| | - Carlos Ferreira Santos
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
- * E-mail:
| |
Collapse
|
5
|
Kusuda Y, Kondo Y, Miyagi Y, Munemasa T, Hori Y, Aonuma F, Tsuka S, Mukaibo T, Masaki C, Hosokawa R. Long-term dexamethasone treatment diminishes store-operated Ca 2+ entry in salivary acinar cells. Int J Oral Sci 2019; 11:1. [PMID: 30602784 PMCID: PMC6315037 DOI: 10.1038/s41368-018-0031-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 05/10/2018] [Accepted: 05/14/2018] [Indexed: 11/09/2022] Open
Abstract
Corticosteroids are used in the treatment of many diseases; however, they also induce various side effects. Dexamethasone is one of the most potent corticosteroids, and it has been reported to induce the side effect of impaired salivary gland function. This study aimed to evaluate the effects of dexamethasone on mouse submandibular gland function to gain insight into the mechanism of dexamethasone-induced salivary hypofunction. The muscarinic agonist carbachol (CCh) induced salivary secretion and was not affected by short-term dexamethasone treatment but was decreased following long-term dexamethasone administration. The expression levels of the membrane proteins Na+-K+-2Cl- cotransporter, transmembrane member 16A, and aquaporin 5 were comparable between the control and long-term dexamethasone treatment groups. The CCh-induced increase in calcium concentration was significantly lower in the presence of extracellular Ca2+ in the long-term dexamethasone treatment group compared to that in the control group. Furthermore, CCh-induced salivation in the absence of extracellular Ca2+ and Ca2+ ionophore A23187-induced salivation was comparable between the control and long-term dexamethasone treatment groups. Moreover, salivation induced by the Ca2+-ATPase inhibitor thapsigargin was diminished in the long-term dexamethasone treatment group. In summary, these results demonstrate that short-term dexamethasone treatment did not impair salivary gland function, whereas long-term dexamethasone treatment diminished store-operated Ca2+ entry, resulting in hyposalivation in mouse submandibular glands.
Collapse
Affiliation(s)
- Yuichiro Kusuda
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan.
| | - Yuta Miyagi
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Yusuke Hori
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Fumiko Aonuma
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| |
Collapse
|
6
|
de Souza Cardoso J, Oliveira PS, Bona NP, Vasconcellos FA, Baldissarelli J, Vizzotto M, Soares MSP, Ramos VP, Spanevello RM, Lencina CL, Tavares RG, Stefanello FM. Antioxidant, antihyperglycemic, and antidyslipidemic effects of Brazilian-native fruit extracts in an animal model of insulin resistance. Redox Rep 2017; 23:41-46. [PMID: 29088999 PMCID: PMC6748693 DOI: 10.1080/13510002.2017.1375709] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Objective: Insulin resistance (IR) plays an important role in the
development of many diseases, such as diabetes mellitus. Therefore, the aim of
the present study was to evaluate the effects of the extracts from fruits native
to Brazil on metabolic parameters and hepatic oxidative markers in an animal
model of insulin resistance induced by dexamethasone (DEX). Methods: Wistar rats received water or extracts of Eugenia
uniflora or Psidium cattleianum, once a day for 21
days. For the last 5 days, the rats received an intraperitoneal injection of
saline or DEX. Results: DEX caused a reduction in body weight gain and relative
pancreatic weight, as well as glucose intolerance, and an increase in serum
glucose and triacylglycerol levels. The extracts were found to prevent
hyperglycemia and hypertriglyceridemia. DEX caused an increase in the levels of
thiobarbituric acid-reactive substances and reactive oxygen species production
in the liver of rats, and both extracts prevented these changes. In addition,
hepatic glutathione peroxidase activity was reduced by DEX. However, total thiol
content and activities of catalase, superoxide dismutase, and
delta-aminolevulinate dehydratase were not altered in any of the tested
groups. Conclusion: Fruit extracts of E. uniflora and
P. cattleianum exhibited considerable
antihyperglycemic, antidyslipidemic, and antioxidant effects, and may be useful
in the therapeutic management of alterations due to IR.
Collapse
Affiliation(s)
- Juliane de Souza Cardoso
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Pathise Souto Oliveira
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Natália Pontes Bona
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Flávia Aleixo Vasconcellos
- b Laboratório de Química Aplicada a Bioativos, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Jucimara Baldissarelli
- c Laboratório de Enzimologia Toxicológica, Centro de Ciências Naturais e Exatas , Universidade Federal de Santa Maria , Santa Maria , Brazil
| | - Marcia Vizzotto
- d Empresa Brasileira de Pesquisa Agropecuária , Centro de Pesquisa Agropecuária de Clima Temperado , Pelotas , Brazil
| | - Mayara Sandrielly Pereira Soares
- e Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Vanessa Plasse Ramos
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Roselia Maria Spanevello
- e Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Claiton Leoneti Lencina
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Rejane Giacomelli Tavares
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| | - Francieli Moro Stefanello
- a Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos , Universidade Federal de Pelotas , Pelotas , Brazil
| |
Collapse
|
7
|
Easley JT, Maruyama CLM, Wang CS, Baker OJ. AT-RvD1 combined with DEX is highly effective in treating TNF-α-mediated disruption of the salivary gland epithelium. Physiol Rep 2017; 4:4/19/e12990. [PMID: 27694530 PMCID: PMC5064142 DOI: 10.14814/phy2.12990] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 09/09/2016] [Indexed: 12/20/2022] Open
Abstract
Sjögren's syndrome (SS) is an autoimmune disorder characterized by chronic inflammation and destruction of salivary and lacrimal glands leading to dry mouth and dry eyes, respectively. Currently, the etiology of SS is unknown and the current therapies have no permanent benefit; therefore, new approaches are necessary to effectively treat this condition. Resolvins are highly potent endogenous lipid mediators that are synthesized during the resolution of inflammation to restore tissue homeostasis. Previous studies indicate that the resolvin family member, RvD1, binds to the ALX/FPR2 receptor to block inflammatory signals caused by tumor necrosis factor-alpha (TNF-α) in the salivary epithelium. More recently, the corticosteroid, dexamethasone (DEX), was shown to be effective in reducing salivary gland inflammation. However, DEX, as with other corticosteroids, elicits adverse secondary effects that could be ameliorated when used in smaller doses. Therefore, we investigated whether the more stable aspirin-triggered (AT) epimer, AT-RvD1, combined with reduced doses of DEX is effective in treating TNF-α-mediated disruption of polarized rat parotid gland (Par-C10) epithelial cell clusters. Our results indicate that AT-RvD1 and DEX individually reduced TNF-α-mediated alteration in the salivary epithelium (i.e, maintained cell cluster formation, increased lumen size, reduced apoptosis, and preserved cell survival signaling responses) as compared to untreated cells. Furthermore, AT-RvD1 combined with a reduced dose of DEX produced stronger responses (i.e., robust salivary cell cluster formation, larger lumen sizes, further reduced apoptosis, and sustained survival signaling responses) as compared to those observed with individual treatments. These studies demonstrate that AT-RvD1 combined with DEX is highly effective in treating TNF-α-mediated disruption of salivary gland epithelium.
Collapse
Affiliation(s)
- Justin T Easley
- School of Dentistry, University of Utah, Salt Lake City, Utah
| | | | | | - Olga J Baker
- School of Dentistry, University of Utah, Salt Lake City, Utah
| |
Collapse
|
8
|
Does laser phototherapy influence the proliferation of myoepithelial cells in the salivary gland of hypothyroid rats? JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2017; 173:681-685. [PMID: 28732334 DOI: 10.1016/j.jphotobiol.2017.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/06/2017] [Accepted: 07/10/2017] [Indexed: 12/28/2022]
Abstract
Thyroid hormones influence both development and growth of organs and tissues and guarantee metabolic demands that interfere with the quality of digestive secretions, including those of the salivary glands. Laser phototherapy - LPT can modulate various biological phenomena and its diverse effects permit the action on different cell types. The aim of this study was to evaluate the influence of laser phototherapy on myoepithelial cells of salivary glands of hypothyroid rats. Forty-two albino Wistar rats were divided into two main groups: euthyroid (EU) and hypothyroid (HYPO). Hypothyroidism was induced using propylthiouracil (PTU) for 4weeks. Each group was divided into subgroups: control (without laser) and laser groups (Red/infrared - IR). LPT was used on the submandibular gland and was carried out using a diode laser (λ660 or λ780nm, 40mW, spot size 0.04cm2, irradiation area 1cm2, 300s, 6J/cm2 per gland, 12J/cm2 per session) and started two weeks after PTU treatment. LPT was repeated every other day for two weeks. After animal death, the glands were removed, dissected and processed for immunohistochemical analysis. It was observed an increase in the number of myoepithelial cells of hypothyroid control rats in comparison to euthyroid controls (p=0.001). Visible LPT (λ660nm) caused significant higher proliferation of myoepithelial cells in EU rats when compared to IR LPT (λ 780nm)(p≤0.001).It is concluded that, despite the LPT protocol used did not influence myoepithelial proliferation on hypothyroid rats it significantly increased the proliferation on euthyroid animals.
Collapse
|