Article

Eye fatigue (Asthenopia) relief by astaxanthin

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Abstract

Astaxanthin is a naturally occurring carotenoid in a wide variety of living organisms such as salmon, shrimp, crab, and red snapper. Approximately 90% of the astaxanthin in krill is found in the eye. Asthenopia, or eye fatigue, is an ophthalmological condition with nonspecific symptoms such as eye pain, eye strain, blurred vision, headache, and shoulder stiffness. Symptoms often occur after reading, computer work, or other activities that involve visual display terminals (VDT). More recently, the advances of information technology (IT), software, and electronics have led to the widespread and habitual use of VDT resulting in higher visual fatigue complains and more sufferers. There is, however, no effective therapeutic approach to date. Eye fatigue is usually caused by straining the ciliary body, the eye muscle responsible for accommodation. We previously reported a randomized double-blind placebo controlled study using VDT workers (n=25 treated vs. 23 placebo). 6mg/day astaxanthin supplementation for 4-weeks significantly improved eye fatigue measuring ocular accommodation by the objective instrument and subjective individual assessment. Here we report further 4 clinical studies with the different measurements and an animal study. The same source of astaxanthin, extract derived from the microalgae Haematococcus pluvialis, was used for all of the studies. The first clinical study was performed under randomized double-blind placebo controlled cross-over conditions using 10 healthy subjects. After a 20-minute near visual task, accommodation contraction and relaxation times were extended in both the astaxanthin and placebo groups. However, accommodation relaxation time in the placebo was significantly longer than in the astaxanthin group, and accommodative contraction and relaxation times after a 10-minute rest in the placebo were also significantly longer those in the astaxanthin group. In the second study, the effects of astaxanthin on accommodative recovery derived from a rest after VDT work were studied using 10 healthy volunteers. 6mg/day astaxanthin supplementation for 2-weeks led to a significant relief in accommodative fatigue induced by 30-minutes of IT work (Nintendo Game Boy). In the third study, 22 middle-aged and elder subjects (mean age: 53.9 years) with complaints of eye strain received 6mg/day astaxanthin. Results showed that the pupillary constriction ratio at week 4 was significantly increased compared to that at week 0. The forth clinical study, using 10 healthy subjects, was performed to investigate the effects of visual fatigue on reaction times. Visual fatigue significantly increases reaction time; however 6 mg/day astaxanthin supplementation for 4-weeks was shown to significantly decrease reaction time. We also investigated the intraocular pharmacokinetics of astaxanthin in an albino rabbit. After 100mg/kg astaxanthin administration in a single dose, astaxanthin was detected in the ciliary body as well as the serum at Tmax of 24h and 9h and Cmax of 79.3ng/g and 61.3ng/ml, respectively. Based on the studies it is suggested that astaxanthin supplementation might be a practical and beneficial approach for eye fatigue relief.

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... The main benefits for human health. "Eye fatigue relieve" (Yamashita, 2009), "skin aging defence" (anti-photoaging) (Tominaga et al., 2012) and "muscle resilience" (sports performance enhancement) (Yamashita, 2011;Earnest et al., 2011) have been most clinically substantiated. ...
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The effect of Astaxanthin powders on biological, health and growth parameter of common carp Cyprinus carpio L. Fish weight varied between (59.2-66.4 g) were studied for 10 weeks. Four treatments (triplicate) were employed as follows: T1: Diet without any addition, T2: adding 2.5 g Astaxanthin powders /kg diet, T3: adding 5 g Astaxanthin powders /kg diet, T4: adding 7.5 g Astaxanthin powders /kg diet. Twice daily feeding at 9:00 a.m. and 2:00 p.m. Blood samples were taken from the caudal vein of fish. The results showed no significant difference between treatments in terms of biological parameter (p>0.05). The results showed a significant difference between treatments in terms of Health indices, including gonadosomatic, but no significant difference (p>0.05) hepatosomatic, spleenosomatic index and Gill index. The results showed a significant difference between treatments in terms of growth performance (p<0.05), including weight gain, Relative growth rate and Specific growth rate. Group results of blood factors showed that between Granulocytes, Lymphocytes and Monocytes there was no significant difference between treatments (p>0.05). Lastly, we found that diets containing higher levels of astaxanthin powders improve the growth performance, biological and GSI in common carp Cyprinus carpio L. Keywords: common carp Cyprinus carpio L., Astaxanthin powders, Biological and Health parameter and growth performance. ABSTRAK Efek Astaxanthin bubuk pada biologis, kesehatan dan pertumbuhan parameter Ikan Mas Cyprinus carpio L. Berat ikan variasi antara (59.2-66.4 GM) dipelajari selama 10 minggu. Empat perlakuan (tiga replikasi) yang digunakan sebagai berikut: T1: diet tanpa penambahan, T2: ditambahkan 2.5 gr bubuk Astaxanthin /kg diet, T3: ditambahkan 5 g bubuk Astaxanthin /kg diet, T4: ditambahkan 7.5 g bubuk Astaxanthin /kg diet. Pemberian pakan dilakukan pada 9:00 a.m dan 2:00 p.m. Sampel darah diambil dari vena caudal ikan. Hasilnya menunjukkan tidak ada perbedaan yang signifikan antar perlakuan dalam hal parameter biologis (p>0.05). Hasilnya menunjukkan perbedaan yang signifikan antara perawatan dalam hal Indeks Kesehatan, termasuk gonadosomatik, tetapi tidak ada perbedaan yang signifikan (p>0.05) hepatosomatic, indeks spleenosomatic dan indeks Gill. Hasilnya menunjukkan perbedaan yang signifikan antara perawatan dalam hal kinerja pertumbuhan (p<0.05), termasuk penambahan berat badan, tingkat pertumbuhan relatif dan tingkat pertumbuhan spesifik. Hasil pengelompokan faktor darah menunjukkan bahwa antara Granulosit, Limfosit dan Monosit tidak memiliki perbedaan yang signifikan antar perlakuan (p>0.05). Terakhir, kami menemukan bahwa diet yang mengandung tingkat yang lebih tinggi dari bubuk Astaxanthin Omni-Akuatika, 15 (2): 52-59, 2019 ISSN: 1858-3873 print / 2476-9347 online Research Article journal homepage: http://ojs.omniakuatika.net 53 Saraddin et al., Biological and Health impact of Astaxanthin powders meningkatkan kinerja pertumbuhan, biologis dan Gonadosomatic index % (GSI) yang umumnya digunaan untuk Cyprinus carpio L. Kata Kunci: ikan mas Cyprinus carpio L., serbuk Astaxanthin, parameter biologis, kesehatan dan kinerja pertumbuhan.
... The main benefits for human health. "Eye fatigue relieve" (Yamashita, 2009), "skin aging defence" (anti-photoaging) (Tominaga et al., 2012) and "muscle resilience" (sports performance enhancement) (Yamashita, 2011;Earnest et al., 2011) have been most clinically substantiated. ...
Article
Full-text available
The effect of Astaxanthin powders on biological, health and growth parameter of common carp Cyprinus carpio L. Fish weight varied between (59.2-66.4 g) were studied for 10 weeks. Four treatments (triplicate) were employed as follows: T1: Diet without any addition, T2: adding 2.5 g Astaxanthin powders /kg diet, T3: adding 5 g Astaxanthin powders /kg diet, T4: adding 7.5 g Astaxanthin powders /kg diet. Twice daily feeding at 9:00 a.m. and 2:00 p.m. Blood samples were taken from the caudal vein of fish. The results showed no significant difference between treatments in terms of biological parameter (p>0.05). The results showed a significant difference between treatments in terms of Health indices, including gonadosomatic, but no significant difference (p>0.05) hepatosomatic, spleenosomatic index and Gill index. The results showed a significant difference between treatments in terms of growth performance (p<0.05), including weight gain, Relative growth rate and Specific growth rate. Group results of blood factors showed that between Granulocytes, Lymphocytes and Monocytes there was no significant difference between treatments (p>0.05). Lastly, we found that diets containing higher levels of astaxanthin powders improve the growth performance, biological and GSI in common carp Cyprinus carpio L. Keywords: common carp Cyprinus carpio L., Astaxanthin powders, Biological and Health parameter and growth performance. ABSTRAK Efek Astaxanthin bubuk pada biologis, kesehatan dan pertumbuhan parameter Ikan Mas Cyprinus carpio L. Berat ikan variasi antara (59.2-66.4 GM) dipelajari selama 10 minggu. Empat perlakuan (tiga replikasi) yang digunakan sebagai berikut: T1: diet tanpa penambahan, T2: ditambahkan 2.5 gr bubuk Astaxanthin /kg diet, T3: ditambahkan 5 g bubuk Astaxanthin /kg diet, T4: ditambahkan 7.5 g bubuk Astaxanthin /kg diet. Pemberian pakan dilakukan pada 9:00 a.m dan 2:00 p.m. Sampel darah diambil dari vena caudal ikan. Hasilnya menunjukkan tidak ada perbedaan yang signifikan antar perlakuan dalam hal parameter biologis (p>0.05). Hasilnya menunjukkan perbedaan yang signifikan antara perawatan dalam hal Indeks Kesehatan, termasuk gonadosomatik, tetapi tidak ada perbedaan yang signifikan (p>0.05) hepatosomatic, indeks spleenosomatic dan indeks Gill. Hasilnya menunjukkan perbedaan yang signifikan antara perawatan dalam hal kinerja pertumbuhan (p<0.05), termasuk penambahan berat badan, tingkat pertumbuhan relatif dan tingkat pertumbuhan spesifik. Hasil pengelompokan faktor darah menunjukkan bahwa antara Granulosit, Limfosit dan Monosit tidak memiliki perbedaan yang signifikan antar perlakuan (p>0.05). Terakhir, kami menemukan bahwa diet yang mengandung tingkat yang lebih tinggi dari bubuk Astaxanthin Omni-Akuatika, 15 (2): 52-59, 2019 ISSN: 1858-3873 print / 2476-9347 online Research Article journal homepage: http://ojs.omniakuatika.net 53 Saraddin et al., Biological and Health impact of Astaxanthin powders meningkatkan kinerja pertumbuhan, biologis dan Gonadosomatic index % (GSI) yang umumnya digunaan untuk Cyprinus carpio L. Kata Kunci: ikan mas Cyprinus carpio L., serbuk Astaxanthin, parameter biologis, kesehatan dan kinerja pertumbuhan.
... The main benefits for human health. "Eye fatigue relieve" (Yamashita, 2009), "skin aging defence" (anti-photoaging) (Tominaga et al., 2012) and "muscle resilience" (sports performance enhancement) (Yamashita, 2011;Earnest et al., 2011) have been most clinically substantiated. ...
Article
Full-text available
The effect of astaxanthin powders on biological, health and growth parameter of common carp Cyprinus carpio L. Fish weight varied between (59.2 –66.4gm)were studied for 10 weeks. four treatments(three replicates/treatment) were employed as follows: T1: Diet without any addition, T2: adding 2.5 gm astaxanthin powders / kg diet, T3: adding 5 gm astaxanthin powders / kg diet, T4: adding 7.5gm astaxanthin powders / kg diet. Twice daily feeding at 9:00 a.m. and 2:00 p.m. should be considered that the feeding rate of biomass weight after each took biometrics. Finally, blood samples were taken from the caudal vein of fish. The results showed no significant difference between treatments in terms of biological parameter (p>0.05). The results showed significant difference between treatments in terms of body indices, including Gonadosomatic, but no significant difference (p>0.05) Hepatosomatic, Spleenosomaticindex and Gill index. The results showed a significant difference between treatments in terms of growth performance (p<0.05), including weight gain, Relative growth rate and Specific growth rate. Group results of blood factors showed that between Granulocytes, Lymphocytes and Monocytes there was no significant difference between treatments (p>0.05). Lastly, we found that diets containing higher levels of Astaxanthin powders improve the growth performance, biological and GSI in common carp Cyprinus carpio L.
... Figure 2 shows the main benefits for human health. "Eye fatigue relieve" [10], "skin aging defense" (anti-photoaging) [11] and "muscle resilience" (sports performance enhancement) [12,13] have been most clinically substantiated. There were the cases that the administration improved the cardiac function in the heart failure patients who is difficult to control with drug therapy and in the patients whose activity levels were reduced because of chronic heart failure resulting in enhancing their daily activity levels and QOL. ...
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To conduct an experimental investigation of the effect of accommodative relaxation using far point shift stimuli for the reduction of asthenopia. Twenty-two female students accommodated to a far point shift stimuli during a 2-min period immediately after a 15-min sustained task on a three-dimensional display. Before and after the trial, their accommodative step response and symptoms were assessed. The far point shift stimuli in the optical system, which were presented on a refractometer, were created by moving the target scenery images from far to near, lineally centred about the far point position of each eye. During 2 min of fixating on the far point shift stimuli, changes in refraction were recorded in the same eye. While looking at the far point shift stimuli, 10 of 22 subjects had changes in refraction that showed a hypermetropic shift, and the other 12 subjects had changes in refraction that showed a myopic shift. The time taken for the accommodative step response from far to near post-trial in the myopic shift group was markedly prolonged, and the accommodative lag at the far target in the optometer was significantly increased. In the myopic shift group, the symptoms of "eye fatigue", "eye pain", "eye heaviness", and "eye dryness" also increased after the trial. In the hyperopic shift group, however, only the symptom of "eye dryness" increased, with no reduction of accommodation function. We suggest that accommodative relaxation by accommodative far point shift stimuli is effective in the reduction of asthenopia.