ABSTRACT
Background Meibomain gland is a specially differentiated sebaceous gland lying in the tarsus of upper and lower eyelid.The morphological changes of the gland is associated with a variety of ocular surface diseases.Studying the relationship of morphological and functional change of meibomain gland with ocular surface is of great significance.Objective This study was to observe the change of morphology,structure and function of meibomain gland over aging and investigate the assocation of meibomain gland abnormality with ocular surface.Methods A prospectively cases-observational study was performed.Ninety-three eyes of 93 patients with age-related cataract aged 45 and older were enrolled in Shanxi Eye Hospital from March to September 2016 under the informed consent.The patients were divided into 45 to 59-year group and ≥60-year group according to age or meibomian gland loss ≥ 1/3 group and meibomian gland loss ＜ 1/3 group.The ocular anterior segment,lid margin,meibomian gland orifices and lipids traits were examined by slit-lamp microscope.The ocular surface symptoms were assessed and scored by Ocular Surface Disease Index (OSDI) scale.The break-up time of tear film (BUT),tear meniscus height,meibomian gland dropout degree,conjunctival hyperemia and corneal fluorescence staining scores were measured using ocular surface analyzer.Results No dry eye symptom was complained in all the subjects,and their OSDI scores were ＜12.No abnormal changes at the lid margin and the muco-cutaneous junction were observed.No abnormality of the meibomian gland orifices,the lipids traits and drainage was observed under the slit-lamp microscope.BUT was shortened in 42 eyes (45.16％);tear meniscus height was lowed in 52 eyes (55.91％);meibomian gland loss range was ≥1/3 in 58 eyes (62.27％).The meibomian gland loss scores were 1.65±0.79 in the 45 to 59-year group and 1.86±0.72 in the ≥60-year group,showing an insignificant difference between them (t =1.301,P =0.197).But when coming to the correlation analysis,a positive correlation was found between meibomian gland loss scores and age (rs =0.323,P=0.002),and no correlations were seen between age and BUT or tear meniscus height (rs =0.154,P =0.141;rs=-0.024,P =0.821).In addition,meibomian gland loss scores showed a negative correlation with mean BUT (rs =-0.251,P =0.015).The eye number of BUT abnormality in the meibomian gland loss ≥ 1/3 group was more than that in meibomian gland loss ＜1/3 group (P =0.018).Conclusions Meibomian gland loss is more serious over aging in middle aged and elderly population,and serious meibomian gland loss increases the risk of tear film instability.The early meibomain gland dysfunction-like signs occur prior to symptoms,which should raise concern in clinical work.
ABSTRACT
Background Statins has prominent roles in regulating lipids,anti-inflammation,autoxidation and protecting vascular endothelial cells.Sartans can promote cell growth and the expression of cytokines.Since the pleiotropic effects of statins and sartans on a variety of cell types,it is inferred that the two medicines can delay retinal aging.Objective This study was to explore the anti-aging effect of simvastatin and telmisartan on the physiological aging of retina.Methods Sixty-six three-month-old healthy SD rats were selected in this study,and 6 of them served as the youth group and the right eyeballs were immediately enucleated.The other rats were raised until 9-month-old in the same conditions and then randomly divided into the simvastatin group,telmisartan group and the control group with 20 rats for each group.The simvastatin of 5 mg/kg and telmisartan of 8 mg/kg were given by intragastric administration once a day in the simvastatin group and the telmisartan group until 17-month-old,and the equal amount of normal saline was used in the control group in the same way.The number of survival rats was 12 in the simvastatin group,10 in the telmisartan group and 8 in the control group.The right eyes were enucleated after heart perfusion of 4％ paraformaldehyde solution for the preparation of retinal paraffin sections.Retinal thickness was measured by pathological examination,and the expressions of the retinal neuron markers,including Thy-1,protein kinase C-α (PKC-ot),opsin and rhodopsin,were detected by immunofluorescence technique to evaluate the morphology of retinal ganglion cells (RGCs),bipolar cells as well as the thickness of the outer segment of photoreceptors.Results The retinal structure was clear in the rats of the youth group.However,the RGCs arrangement and inner segment (IS) and outer segment (OS) structure were abnormal in the simvastatin group,the telmisartan group and the control group.Compared with the rats of the youth group,the thickness of outer nuclear layer (ONL),outer plexiform layer (OPL),inner nuclear layer (INL),inner plexiform layer (IPL) and the total thickness of the aging rats were decreased,and the IS/OS thickness was increased in the simvastatin group and the telmisartan group (all at P＜ 0.01).Thy-1 stain showed that the number of RGCs was reduced in the simvastatin group,telmisartan group and the control group compared with the youth group,and that in the simvastatin group was increased in comparison with the control group (all at P＜0.01).PKC-αt stain exhibited that the density of bipolar cells was increased but the axon terminal bouton was declined in the simvastatin group,telmisartan group and the control group compared with the youth group,and the axon terminal bouton was declined in the simvastatin group compared with the youth group and the control group (all at P=0.000).Opsin and rhodopsin stains displayed that the OS thickness was increased in the simvastatin group,telmisartan group and the control group compared with the youth group,and that in the telmisartan group was reduced in comparison with the control group (all at P＜0.01).Conclusions As SD rat aging,retinal thickness is gradually attenuated and the number of RGCs is gradually declined.Although the density of bipolar cells seem to be unchanged,their synaptic connections are decreased and the OS is thicken.Simvastatin and telmisartan can delay retinal senescence by protecting retinal neurons against aging and thinning thickened OS.
ABSTRACT
Objective To investigate the relationship between exposure intensity and illumination time of blue light and replicative senescence of rat retinal pigment epithelial (RPE) ceils.Methods Thirty-six 12-14 weeks Wistar rats were kept in the cage with a blue-light bulb [(450±10) nm],and were randomly divided into four groups (no light,nature light,500 lx light and 1000 lx light illumination),each has nine rats.The rats in each group were further divided into three subgroups according to illumination time (one month,two months or three months).Eyeballs were collected after intraperitoneal injection of 10% chloral hydrate.The right eye of each rat was embedded in paraffin and sectioned for hematoxylin-eosin (HE)staining,while frozen sections of the left eye were stained for the senescence-associated β-galactosidase (SA-β-Gal).The data were analyzed by SPSS11.5 statistical software.Results The amounts of SA-β-Gal positive RPE cells were significantly different between all groups under the same illumination time 17 (P=0.000),and between all subgroups of different illumination time with same exposure intensity (P＜0.01)except for the control group (no light).Conclusion Blue-light can induce replicative senescence in rat RPE cells in an intensity and time-dependent manner.