Abstract
The pathogenesis of myopia remains unclear. Both genetic and environmental factors play a role in the disease progression. Reasons including reduced physical activity (PA) and low-grade intraocular inflammation may be involved in the development of myopia. To analyze the levels of irisin, brain-derived neurotrophic factor (BDNF) and other intraocular cytokines in aqueous humor of high myopia patients, and to evaluate the roles of PA and inflammation in developing myopia. We collected aqueous humor samples from patients with axial length (AL) over 26 mm (n = 35) or shorter than 25 mm (n = 38) during cataract extraction surgery. Samples were assayed using the enzyme-linked immunosorbent assay (ELISA) kit for irisin and a multiplex immunoassay kit for BDNF, interleukin (IL)-6, IL-8 and IL-10, and tumor necrosis factor alpha (TNF-α). Irisin levels in the aqueous samples of the highly myopic eyes were significantly higher than in the control group (p = 0.027). The BDNF levels of the highly myopic group were significantly lower than in the control group (p = 0.043). Median level of leukemia inhibitory factor (LIF) for highly myopic group (2.035 pg/mL) was statistically significantly higher than in the control group (0.750 pg/mL) (U = 210.5, Z = -4.495, p < 0.001). Interleukin 1 receptor antagonist (IL-1ra) level in the aqueous samples of the highly myopic group was significantly lower than in the shorter AL group (p = 0.049). Interleukin 6, IL-8 and IL-10 levels were not significantly different between the 2 groups (p = 0.501, p = 0.059 and p = 0.192, respectively). Tumor necrosis factor α levels could only be detected in 30 samples and median levels in the 2 groups were not statistically significantly different (U = 99, Z = -0.482, p = 0.650). No correlation was found between IL-6, IL-8, IL-10 and TNF-α, and the AL (p > 0.05). Irisin was positively correlated with AL (p = 0.028, r = 0.287). The BDNF was negatively correlated with AL (p = 0.040, r = -0.246). Interleukin 1ra was negatively correlated with AL (p = 0.038, r = -0.276). There was also a correlation between LIF and AL (p < 0.001, r = 0.486). Higher irisin level in high myopia group opens a new direction to discover the relationship between PA and myopia. The decreased BDNF in high myopia group probably demonstrates the connection between myopia and neurodegenerative disease.
Highlights
Higher irisin level in high myopia group opens a new direction to discover the relationship between physical activity (PA) and myopia
The decreased brain-derived neurotrophic factor (BDNF) in high myopia group probably demonstrates the connection between myopia and neurodegenerative disease
The result of our study showed that the leukemia inhibitory factor (LIF) level in the long axial length (AL) group was significantly higher than in the control, and LIF was significantly positively correlated with the AL (r = 0.486), indicating that this protective factor was connected with axial myopia progression
Summary
Both genetic and environmental factors play a role in the disease progression. The pathogenesis of this disorder remains unclear It has been speculated that lifestyle changes such as reduced physical activity (PA), reduced time spend outdoors and more indoor work might be the reason of myopia progression.[5] Irisin,[6] as an exercise-induced myokine, is secreted into the circulation after proteolytic cleavage from fibronectin-type III domain containing 5 (FNDC5). The physiological function of irisin is to convert white adipose tissue to brown, which increases energy expenditure.[6] Physical activity is wellknown as a protective lifestyle feature against type 2 diabetes mellitus (T2DM), cardiovascular diseases, cancer, dementia, and depression.[7] The protective role of PA against myopia has been an area of interest in recent years. As an exercise-induced myokine, may be involved in the relationship of PA and myopia progression
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Advances in clinical and experimental medicine : official organ Wroclaw Medical University
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
