Effects of 530 nm monochromatic light on basic fibroblast growth factor and transforming growth factor-β1 expression in Müller cells

AIMTo expose rat retinal Müller cells to 530 nm monochromatic light and investigate the influence of varying light illumination times on basic fibroblast growth factor (bFGF) and transforming growth factor-β1 (TGF-β1) expression.METHODSThree groups of rat retinal Müller cells cultured in vitro under a 530 nm monochromatic light were divided into 6, 12 and 24h experimental groups, while cells incubated under dark conditions served as the control group. The bFGF and TGF-β1 mRNA expression, protein levels and fluorescence intensity of the Müller cells were analyzed.RESULTSThe bFGF mRNA expression and protein levels were significantly upregulated in Müller cells in all three experimental groups compared with the control group (P<0.05), while that of TGF-β1 was downregulated (P<0.05). Also, bFGF expression was positively correlated, but TGF-β1 expression was negatively correlated with illumination time. The largest changes for both cytokines were seen in the 24h group. The changes in bFGF and TGF-β1 fluorescence intensity were highest in the 24h group, and significant differences were observed among the experimental groups (P<0.05).CONCLUSIONThe expressions of bFGF and TGF-β1 changed in a time-dependent manner in Müller cells exposed to 530 nm monochromatic light with 250 lx illumination intensity. Müller cells might play a role in the development of myopia by increasing bFGF expression or decreasing TGF-β1 expression. Changes in cytokine expression in retinal Müller cells may affect monochromatic light-induced myopia.

The Response of Bio-Component Production of Nannochloris oculata to the Combinations of Monochromatic Light

Illuminating conditions are crucial factors affecting the microalgal growth and biosynthesis.The effects of illuminating spectral quality on the growth and bio-component production of Nannochloris oculata were investigated.The results indicated that a high proportion of Red-light enhanced the pigments and carbohydrate production but reduced those of the biomass and lipid.Mono-chromatic Blue-light has advantageous effects on lipid production compared with Red-and White-light.The optimal light spectrum for the protein production was the combination of Red-and Blue-light at a ratio of 4:3 or 5:2.Among the seven fatty acids identified from N.oculata,the contents of C16:0,C18:0,and C18:3(n-3)in the lipid were inhibited by the increased proportion of Red-light while those of C18:2(n-9),C16:2(n-6),and C20:0 were inhibited by Blue-light.Monochromatic Red-and Blue-light and their com-binations were proposed as a promising illuminating strategy for the large-scale cultivation aiming for various bio-components.

Monochromatic green light stimulation during incubation shortened the hatching time via pineal function in White Leghorn eggs

Background:Effect of monochromatic green light illumination on embryo development has been reported in chickens.The avian pineal gland is an important photo-endocrine organ formed by a mediodorsal protrusion during embryonic development.However,the involvement of pineal gland in the light transduction process remains to be elucidated.In the present study,we investigated the influence of monochromatic green light on hatching time and explored the possible mechanism via pineal function.Results:A total of 600 eggs of White Leghorn(Shaver strain)were incubated under photoperiods of either 12 h of light and 12 h of darkness using monochromatic green light(12L:12D group)or 24 h of darkness(0L:24D group)for 18 d.Compared to 0L:24D group,the green light stimulation shortened the hatching time without extending the hatch window or impairing hatchability.The liver of embryos incubated in the 12L:12D light condition was heavier than those of the 0L:24D group on d 21 post incubation which may be linked to the observed increase in the serum concentration of insulin-like growth factor 1(IGF-1);primary secretion of the liver.Histological structure analysis of pineal gland demonstrated that the light stimulation increased follicle area,wall thickness and lumen area on d 10 and d 12 post incubation.Rhythmic function analysis demonstrated that three clock related genes(brain and muscle ARNT-like-1,BMAL1;circadian locomotor output cycles kaput,CLOCK;and cryptochrome-1,CRY1)and a melatonin rate-limiting enzyme related gene(arylalkylamine N-acetyltransferase,AANAT)were rhythmically expressed in the pineal gland of the 12L:12D group,but not in the 0L:24D group.Simultaneously,the light stimulation also increased the concentration of melatonin(MT),which was linked to hepatocyte proliferation and IGF-1 secretion in previous studies.Conclusions:The 12L:12D monochromatic green light stimulation during incubation shortened hatching time without impairing hatching performance.Pineal gland’s early histological development and maturation of its rhythmic function were accelerated by the light stimulation.It may be the key organ in the photo-endocrine axis that regulates embryo development,and the potential mechanism could be through enhanced secretion of MT in the 12L:12D group which promotes the secretion of IGF-1.

A Fundus Photographic Method with Narrow Spectral Band Luminance

We perfected the narrow spectral band fundus photographic system using interference filters at the wavelengths of 417, 478, 500, 530, 547, 570, 589, 607, 628 and 648nm. Tests about the light penetration of filters and exposure of various brand films were made on this system. Studies of the contrast of fundal tissues and structures under the different narrow spectral band light were made on 43 Chinese fellow eyes. The results indicates that the interference filters of 570 nm have the highest light penetr...