THE EFFECT OF MODERATE EXERCISE ON VASCULAR ENDOTHELIAL GROWTH FACTOR EXPRESSION DURING TOOTH SOCKET WOUND HEALING AFTER TOOTH EXTRACTION.
Objective: To determine vascular endothelial growth factor (VEGF) expression during the tooth socket wound healing process post-extraction after moderate exercise.
Methodology: Wistar Rats (Rattus norvegicus) were divided into control group (group I) and treatment group (group II). The group II was given moderate exercise with 50% maximal work capacity of time, every day, for 2 weeks. The VEGF expression was observed in macrophages 3 days after tooth extraction and analyzed using immunohistochemistry. Statistical analysis was conducted using an independent t-test.
Results: The treatment group had a higher expression of mean VEGF as compared to the control group (194.43 +17.213 vs. 131.29 +21.085, respectively). The difference in test results of VEGF expressions was significant, with a p value of =0.000.
Conclusion: Moderate exercise increased the expression of VEGF during the tooth socket wound healing process after tooth extraction.
Key Words: Moderate exercise, Vascular endothelial growth factor, Wound healing, Wistar rats
The most common dental treatments or procedures performed by the dentists in the Indonesia are tooth extractions that can lead to alveolar bone defect1. According to health-related statistics 2016, the percentage of dental treatments culminating in tooth extraction reached as high as 80.6%2. Previous research highlighted the prevalence of tooth extraction-related complications such as fractures 31.82%, bleeding 4.54% and swelling 2.27%3.
However, some will heal through a primary healing process without complications. The complex and dynamic process of replacing devitalized missing cellular structures and tissue layers is known as wound healing. It is achieved through hemostasis, inflammation, proliferation and remodeling. Injury caused by tooth extraction is categorized as acute inflammation that can occur about 1-3 days and chronic inflammation can occur if the inflammation duration prolonged about 4-5 days. There are many factors that can affect wound healing and may cause improper or impaired tissue repair. The process of wound healing can sometimes be delayed, especially in patients who have to consume certain drugs (anticoagulants) or in patients who have a systemic disease (diabetes) or other external and internal factors4,5.
The growth factor which stimulates angiogenesis and vasculogenesis is called vascular endothelial growth factor (VEGF). VEGF has critical role in the new bone formation, hematopoiesis and wound healing. VEGF can be produced by neutrophils, macrophages and platelets. Exercise may stimulate the secretion of VEGF6.
Exercise can be defined as an activity that can improve or maintain health. Regular exercise can provide lots of benefits including strengthening of skeletal muscles, improving cardiovascular functions, losing weight and maintaining body health. In addition, physical exercise can also prevent cancer by inhibiting the formation of transform cells. Exercise generally can be divided into 2 types, aerobic and anaerobic. Aerobic exercise such as swimming will enhance the overall oxygen consumption of the body7,8. The several pathways that are induced by exercise are known to be important for vasculogenesis and angiogenesis. Moderate exercise has been shown to increase VEGF expression. VEGF has critical role in wound healing and vasculogenesis. In addition to mitogen-activated protein kinase (MAPK), the several other signaling pathways that may be the link between metabolism and vasculogenesis are activated by moderate exercise.
The activation of several downstream signaling proteins including calmodulin-dependent kinase (CaMK) and CaN by the increasing Ca++ level, possibly lead to increased VEGF mRNA expression9. Previous studies showed that physical exercise can increase the expression of VEGF. A study conducted by Erekat et al10 reported that the expression of cardiac VEGF is significantly increased (p0.05 for both groups, therefore it can be concluded that the two groups were normally distributed. After the normality test, a homogeneity test was then performed with the Levene test to determine whether the two groups were homogeneous or not. The results of the Levene test showed that p >0.05 for both groups, therefore it can be concluded that the two groups were homogeneous.
After finding out that the two groups were normally distributed and homogeneous, an independent t-test was conducted The data obtained were analyzed using SPSS version 21.0 (SPSS Inc., Illinois, Chicago). The independent t-test was conducted to analyze the difference between 02 groups (group I and group II). A p value of <0.05 was considered significant.
According to our results, the treatment group had a higher expression of VEGF as compared to the control group. The treatment group showed a mean of its VEGF expression as 194.43 and the control group showed a mean of its VEGF expression as 131.29. Table 1 shows the difference in test results of VEGF expressions between the two groups, with a p value of =0.000.
On the immunohistochemical preparations of tooth extraction sockets in Wistar rats' mandible, the observed cells were macrophages that secreted VEGF. The control group showed that its macrophage VEGF expression was lower than that of the treatment group (Figure 1 and Figure 2).
Wound healing begins when the tissue is injured. In this study, the wound is a tooth-shaped socket formed from the extraction of Wistar rats' mandibular incisors. Healing time depends on several factors in wound healing process. One of the most important factors is angiogenesis. In hemostasis and inflammation phases, some cells will produce VEGF which may accelerate wound healing process5,6.
The results of this study were in accordance with the previous study by Vital et al11. There was an increased VEGF expression in the 60-year-old patient after physical exercise (in 4 samples), while the other 6 samples did not affect VEGF expression. This study is also in accordance with the study done by Jensen et al12 on skeletal muscle in humans and showed that physical exercise for 4 weeks can induce VEGF mRNA. Physical exercise has a lot of benefits such as increased heart and lung capacity, joint and muscle strength, decreased levels of body fat and blood glucose levels, reduced risk of coronary heart disease, as well as immunity modulation. It can thus help in optimization of physiological performance13. Regular physical exercise can reduce inflammatory markers in wound healing process. Decreased inflammation will help faster wound healing process14.
The physical exercise has anti-inflammatory effect that can be obtained via decrease in visceral fat mass, decrease in the Toll-like receptors (TLRs) expression on macrophages and monocytes and release of anti-inflammatory cytokines. Several studies have revealed that anti-inflammatory effects of physical exercise can inhibit infiltration of macrophages and monocytes to the tissues. Previous studies also showed that physical exercise may decrease the number of monocytes and decrease the number of macrophages in the circulation15,16.
Table 1: Independent t-test between the 2 groups
Macrophages are functionally and phenotypically different in response to various stimuli. Macrophages can be classified phenotypically by the expression of its cell surface molecules, cytokine expression and effector function. Macrophages are divided into the M1 (pro-inflammatory macrophages) and M2 (reparative macrophages). Interleukin-1[beta] (IL-1[beta]), IL-6, IL-12, tumor necrosis factor [alpha] (TNF-[alpha]) and other pro-inflammatory cytokines are triggered by M1. On the other hand, the antiinflammatory cytokines e.g. tumor growth factor [beta] (TGF-[beta]) and IL-10 are produced by M2. M2 macrophages can also secrete VEGF that has important role in the process of neovascularization and wound healing12. Previous studies have shown that there was a relationship between physical exercise and increased expression of VEGF in certain age groups, but the ideal type of physical exercise is debatable17,18.
M2 macrophages within the tissues will be more efficient in wound healing process posttooth extraction because M2 macrophages may produce angiogenic factors such as VEGF. Regular exercise can increase adrenaline which helps open the Ca++ channels in the cell membranes of macrophages which ultimately lead to increased concentration of Ca++ in the cytoplasm. This will activate MAPK through Src and Ras-GAP signal transduction pathway. Consequently, the activated MAPK will activate the mRNA transcription factor for VEGF. Increased synthesis of VEGF will induce translation in ribosomes that will generate new VEGF11,13,19.
Physical activity can also stimulate macrophages on existing wound tissue to produce nitric oxide (NO)20. NO is important for physiological and pathological conditions21. It can increase VEGF through hypoxia-inducible factor 1[alpha] (HIF-1[alpha]). HIF-1[alpha] can be regarded as one of the transcription factors involved in the wound healing process22. During the wound healing process, activated macrophages need high oxygen consumption therefore it will decrease the level of oxygen in the surrounding tissue. This condition will lead to hypoxia. Hypoxia stimulates the formation of new blood vessels and increased HIF-1[alpha] level in the injured area. The dimerization of HIF-1[alpha] and HIF-1[beta] and binding to cis-acting hypoxia response elements (HREs) HREs can increase the expression of VEGF. HIF-1[alpha] expression has an important role in cell regulatoion during hypoxia. Moreover, it can increase the expression of several genes involved in wound healing and angiogenesis23,24.
The function of a system of gene regulation of HIF-1/HRE, which is active in the state of hypoxia, is a proposed mechanism for expression of a specific gene target25,26.
Moderate exercise increased the expression of VEGF during the tooth socket wound healing process after tooth extraction.
1. Sukotjo C, Lin A, Song K, Ogawa T, Wu B, Nishimura I. Oral Fibroblast Expression of Wound Inducible Transcript-3.0 (wit3.0) Accelerates the Collagen Gel Contraction In Vitro. J Biol Chem 2003; 278:27-34.
2. Ministry of Health Republic of Indonesia. Health Profile in Indonesia 2014. Ministry of Health Republic of Indonesia. Sekretaris Jenderal Jakarta; 2015.
3. Lande R, Kepel BJ, Siagian KV. Profile of Risk Factor and Complication of Tooth Extraction at RSGM PSPDG-FK Unsrat. Jurnal E-Gigi 2015; 3:1-6.
4. Guo S, DiPietro LA. Factors Affecting Wound Healing. J Dent Res 2010; 89:219-29.
5. Miloro M, Ghali G, Larsen PE, Waite PD. Peterson's principles of oral and Maxillofacial surgery. BC Decker Hamilton: London; 2004:4-12.
6. Simon, Patrick E. Skin Wound Healing. Available at:"http:// emedicine.medscape.com-/article/884594-overview#". Accessed 04/06/2016.
7. Bao P, Kodra A, Tomic-Canic M, Golinko MS, Ehrlich HP, Brem H. The Role of Vascular Endothelial Growth Factor in Wound Healing. J Surg Res 2009; 153:347-58.
8. Brooks GA, Fahey T, Baldwin KM. Exercise Physiology. 4th edition. Mountain View, California: Mayfield Publishing; 2004:45-9.
9. Ohno H, Shirato K, Sakurail T, Ogasawara J, Sumitani Y, Sato S et al. Effect of exercise on HIF-1 and VEGF signaling. J Phys Fitness Sports Med 2012; 1:5-16.
10. Erekat NS, Al Jarrah MD, Al Khatib AJ. Treadmill Exercise Training Improves Vascular Endothelial Growth Factor Expression in the Cardiac Muscle of Type I Diabetic Rats. Cardiol Res 2014; 5:23-9.
11. Vital TM, Stein AM, de Melo Coelho FG, Arantes FJ, Teodorov E, Santos-Galduroz RF. Physical exercise and vascular endothelial growth factor (VEGF) in elderly: A systematic review. Arch Gerontol Geriatr 2014; 59:234-9.
12. Jensen L, Pilegaard H, Neufer PD, Hellsten Y. Effect of acute exercise and exercise training on VEGF splice variants in human skeletal muscle. Am J Physiol Regul Integr Comp Physiol 2004; 287:R397-402.
13. Irmawati A. The inhibition mechanism of transform cell synthesize on squamous epithelial cell by moderate exercise. Dissertation. Universitas Airlangga 2015; 1-5:93-6.
14. Smith PD, MacDonald TT, Blumberg RS. Principles of Mucosal Immunology. London: Garland Science; 2013:529. Available at: https://books.google.com.pk/books?id=3AgPBAAAQBAJandprintsec=frontcoverandd-q=Principles+of+Mucosal+Immunologyandhl=enandsa=X-andved=0ahUKEwih_76V6enZAhWFXRQKHQcnCBwQ6AEIJjAA#v=onepageandq=Principles%20of%20Mucosal%20Immunologyandf=false
15. Department of Health and Human Services. Your Guide to Physical Activity and Your Heart. National Institutes of Health, National Heart, Lung, and Blood Institute: US; 2006:1-2.
16. Keylock KT, Young H. Delayed Wound Healing: Can Exercise Accelerate it? Int J Exercise 2010; 3:70-8.
17. Gleeson M, Bishop NC, Stensel DJ, Lindley MR, Mastana SS, Nimmo MA. The Anti-Inflammatory Effects of Exercise: Mechanisms and Implications for the Prevention and Treatment of Disease. Nat Rev Immunol 2011; 11:607-15.
18. Autieri MV. Pro and anti-Inflammatory cytokine networks in atherosclerosis. ISRN Vasc Med 2012:1-17.
19. Richardson RS, Wagner H, Mudaliar SR, Saucedo E, Henry R, Wagner PD. Exercise Adaptation Attenuates VEGF Gene Expression in Human Skeletal Muscle. Am J Physiol Heart Circ Physiol 2000; 279:H772-8.
20. Wrenshall LE, Stevens BR, Cerra FB, Platt JL. Modulation of Macrophage and B Cell Function by Glycosaminoglycans. J Leukoc Biol 1999; 66:391-400.
21. Frank S, Kampfer H, Wetzler C, Pfeilschifter J. Nitric oxide drives skin repair: Novel functions of an established mediator. Kidney Int 2002; 61:882-8.
22. Kuwabara M, Kakinuma Y, Ando M, Katare RG, Yamasaki F, Doi Y et al. Nitric Oxide Stimulates Vascular Endothelial Growth Factor Production in Cardiomyocytes Involved in Angiogenesis. J Physiol Sci 2006; 56:95-101.
23. Abaci HE, Truitt R, Tan S, Gerecht S. Unforeseen Decreases in Dissolved Oxygen Levels Affect Tube Formation Kinetics in Collagen Gels. Am J Physiol Cell Physiol 2011; 301:431-40.
24. Conde E, Alegre L, Blanco-Sanchez I, Saenz-Morales D, Aquado-Fraile E, Ponte B et al. Hypoxia Inducible Factor 1-Alpha (HIF-1 Alpha) Is Induced during Reperfusion after Renal Ischemia and Is Critical for Proximal Tubule Cell Survival. PLoS one 2012; 7:e33258.
25. Goggins JB, Chaney C, Radford-Smith LG, Horvat JC, Keely S. Hypoxia and integrin-mediated epithelial restitution during mucosal inflammation. Front Immunol 2013; 4:272.
26. Post DE, Van Meir EG. A Novel Hypoxia-Inducible Factor (HIF) Activated Oncolytic Adenovirus for Cancer Therapy. Oncogene 2003; 22:2065-72.
|Printer friendly Cite/link Email Feedback|
|Publication:||Journal of Postgraduate Medical Institute|
|Date:||Mar 31, 2018|
|Previous Article:||MATERNAL PARENTING AND DEPRESSION IN FEMALE VICTIMS OF DOMESTIC VIOLENCE OF RURAL AREAS OF PUNJAB, PAKISTAN.|
|Next Article:||COMPARISON BETWEEN 0.5% AND 0.75% HYPERBARIC BUPIVACAINE GIVEN INTRA-THECALLY IN ELECTIVE CAESAREAN SECTION.|