Abstract
In this study, we investigated the effects of Perilla frutescens var. acuta aqueous extract (PFA) on eyestrain using in vitro, ex vivo, and clinical tests. We confirmed the antioxidant activity of compounds present in the extract by using high-performance liquid chromatography. PFA contains antioxidant compounds such as rosmarinic acid, luteolin-7-O-glucuronide, and apigenin-7-O-glucuronide, and has been shown to inhibit reactive oxygen species generation in C2C12 muscle cells. In an ex vivo study, PFA inhibited the carbachol (100 μM)-induced contraction of ciliary muscle from rabbit eyeball. We then investigated the mechanism by which PFA caused muscle relaxation and found that it effectively increased cyclic GMP production and inhibited PDE5A activity, but did not affect the cyclic AMP pathway, in cultured human aortic smooth muscle cells. In addition, PFA (50, 100, and 200 µg/mL) dose-dependently decreased basal intracellular calcium in smooth muscle cells and attenuated the endothelin-1-stimulated increase in intracellular calcium. Finally, we performed a clinical study to evaluate the effects of PFA on the near point of accommodation (NPA) after visual display terminal (VDT) work. Thirty participants were randomized to either PFA (500 mg/day) or placebo, and intake for one consecutive week. NPA was evaluated before and after 2 h of VDT work, and was found to be improved in the PFA-treated group. Thus, our findings show that PFA may ameliorate visual fatigue.
Highlights
Eye fatigue has been steadily increasing in recent years, with the growing use of visual display terminals (VDT) such as computers and smartphones [1,2,3]
Research conducted at the National Institute for Occupational Safety and Health (NIOSH) showed that over 50% of frequently VDTs users reported visual fatigue and other ocular problems associated with VDT use [6]
We investigated the effects of PFA on of Reactive oxygen species (ROS) generation in smooth muscle cells to confirm the antioxidant activity of its constituents, as well as its ability to cause relaxation in rabbit ciliary body muscle through the cyclic GMP (cGMP) pathway
Summary
Eye fatigue has been steadily increasing in recent years, with the growing use of visual display terminals (VDT) such as computers and smartphones [1,2,3]. The symptoms of eye fatigue include ocular pain, dry eye sensation, headache, dizziness, ghost images, eye pain, dryness, heavy eyelids, and blurred vision [4,5]. Research conducted at the National Institute for Occupational Safety and Health (NIOSH) showed that over 50% of frequently VDTs users reported visual fatigue and other ocular problems associated with VDT use [6]. Some studies have reported that certain natural plant-derived extracts, including bilberry, Haematococcus pluvialis, blackcurrant, and black soybean hull extracts, can ameliorate visual fatigue and exert antioxidant effects [2,7,9].
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 callDisclaimer: 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.
