PURPOSE: To investigate the asymmetry of the retinal nerve fiber layer thickness (RNFLT) with respect to the horizontal and vertical meridian and between the right and left eye in normal subjects. METHODS: The RNFLT was measured in 121 normal volunteers by optical coherence tomography (OCT). The RNFLT was analyzed by dividing the circle scanning area (diameter 3.4 mm) around the optic disc into 4 quadrants and 12 sectors. RESULTS: There was a significant difference between the RNFLT of the nasal and temporal quadrant in individual eyes. There was a significant difference between the RNFLT of corresponding sectors with respect to the vertical or horizontal meridian in individual eyes. The nasal and temporal RNFLTs were asymmetrical between the right and left eye in the quadrant and sector analysis. The RNFLT of the nasal and temporal quadrant was thicker in the right eye. The nasal and inferior RNFLT measured by OCT had a significant correlation with degree of refractive error. CONCLUSIONS: In normal subjects without significant anisometropia, there was significant asymmetry of the RNFLT for each eye as well as between the right and left eye.
*Tomography, Optical Coherence ; Retinal Ganglion Cells/*ultrastructure ; Retina/*cytology ; Reference Values ; Optic Disk/cytology ; Nerve Fibers/*ultrastructure ; Male ; Humans ; Female ; Adult

OBJECTIVETo investigate the impacts of steady high-glucose or fluctuated glucose conditions on glutamate (Glu) release in purified retinal ganglion cells (RGCs) cultured in vitro, and the effect of serum contained Chinese drugs for nourishing Shen and activating blood (S-NSAB) on it.

METHODSRGCs of neonatal SD rats were cultured by antibody combined two-step purified method in different conditions: the simulated normal condition, the steady high-glucose condition and the fluctuated glucose condition, and they were intervened with S-NSAB. Thereby, the experiment was carried out in 6 groups, i.e. the normal control group (A), the S-NSAB intervened group (B), the steady high-glucose cultured group (C), the steady high-glucose cultured and S-NSAB intervened group (D), the fluctuated glucose cultured group (E), and the fluctuated glucose cultured and S-NSAB intervened group (F). Content of Glu in the extracellular fluid was detected at 24, 48 and 72 h after intervention with a full-automatic biochemical analyzer. And the data obtained were statistically analyzed with SPSS 13.0 soft ware.

RESULTSRelease of Glu at 24 h after intervention in Group E (256.33 +/- 25.73 mg/L) was obviously higher than that in Group A and Group C (134.22 +/- 9.14 mg/L and 141. 17 +/- 22.13 mg/L, P < 0.05); at 24 h and 72 h in Group B (124.50 +/- 10.30 mg/L and 30. 17 +/- 2.97 mg/L) was obviously lower than in Group A respectively (P < 0.05); in Group D at 24 h (127.50 +/- 16.94 mg/L), 48 h (26.17 +/- 3.99 mg/L) and 72 h (27.67 +/- 3.49 mg/L) were lower than in Group C; in Group F at 24 h (228.33 +/- 18.41 mg/L) and 72 h (28.00 +/- 2.41 mg/L) were lower than in Group E respectively at the corresponding time points.

CONCLUSIONSFluctuated glucose condition could obviously increase the Glu release of RGCs, to cause extracellular large amount Glu accumulation, which induces the exciting neurotoxicity to RGCs and finally to aggravate the injury on cells. S-NSAB could reduce the Glu release to some extent in the steady-high or fluctuated glucose conditions, diminish the injury of RGCs from exciting neurotoxicity of Glu, and it might be one of the intervening pathways of Chinese drugs for NSAB in preventing and treating DRP.

Animals ; Animals, Newborn ; Cells, Cultured ; Diabetic Retinopathy ; prevention & control ; Drugs, Chinese Herbal ; pharmacology ; Glucose ; pharmacology ; Glutamic Acid ; metabolism ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells ; cytology ; metabolism

OBJECTIVETo investigate the effect of serum contained Chinese drugs for nourishing Shen and activating blood (S-NSAB) on activity of purified retinal ganglion cells (RGCs) cultured in high glucose medium.

METHODSPurified RGCs of SD rats were cultured in stimulative stable high glucose (50 mmol/L) condition (SHG) and fluctuated glucose condition (FGC) separately, they were intervened with S-NSAB, and the lactate dehydrogenase (LDH) leakage was detected by spectrophotometer for estimating the activity of RGCs.

RESULTSLDH leakage (U/L) in SHG culture was 1 349.17 +/- 215.50 at 24 h, 1220.24 +/- 124.53 at 48 h and 1982.14 +/- 219.03 at 72 h, all significantly lower than that in normal control at the corresponding time points (1628.10 +/-122.10, 1484.13 +/- 127.55 and 2155.75 +/- 140.44, respectively, P<0.05), whereas it was obviously higher in FGC culture at 72 h (2299.60 +/- 88.35), showing that LDH leakage in FGC was significantly higher than that in SHG at the corresponding time points (P<0.05). The LDH leakage was obviously decreased by Chinese medicine intervention with S-NSAB both in SHG at 72 h (1797.62 +/- 146.40) and in FGC at 48 h (1259.92 +/- 87.74) and 72 h (1940.40 +/- 155.47), the difference between pre- and post-intervention was significant (P<0.05).

CONCLUSIONFluctuated glucose conditions of culture medium could obviously damage the membranous stability of RGCs to enhance their permeability and lower the activity of cells; S-NSAB could improve these abnormalities in either SHG or FGC condition, which may be one of the important mechanisms of Chinese formula for nourishing Shen and activating blood in preventing and treating diabetic retinopathy.

Animals ; Animals, Newborn ; Cell Survival ; drug effects ; Cells, Cultured ; Culture Media ; pharmacology ; Drugs, Chinese Herbal ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells ; cytology ; drug effects ; Serum

PURPOSE: To evaluate the association between age and peripapillary retinal nerve fiber layer (RNFL) thickness measured by Cirrus high-definition (HD) spectral domain optical coherence tomography (OCT) in healthy Korean subjects. METHODS: A total of 302 eyes from 155 healthy Korean subjects (age range, 20 to 79 years) underwent RNFL thickness measurements using the Cirrus HD-OCT. Average, quadrant, and clock-hour RNFL thickness parameters were analyzed in terms of age using linear mixed effect models. RESULTS: Average RNFL demonstrated a slope of -2.1 microm per decade of age (p < 0.001). In quadrant analysis, superior (-3.4 microm/decade, p < 0.001) and inferior (-2.9 microm/decade, p < 0.001) quadrants showed steeper slopes, whereas temporal (-1.1 microm/decade, p < 0.001) and nasal (-1.0 microm/decade, p < 0.001) quadrants revealed shallower slopes. Among the 12 clock-hour sectors, clock hours 6 (-4.5 microm/decade, p < 0.001) and 1 (-4.1 microm/decade, p < 0.001) showed the greatest tendency to decline with age; RNFLs of the 3 (-0.2 microm/decade, p = 0.391) and 4 (-0.6 microm/decade, p = 0.052) o'clock hour sectors did not show significant decay. CONCLUSIONS: RNFL thickness was associated with age, especially in superior and inferior areas. The topographic distribution of correlation between age and RNFL thickness was not uniform.
Adult ; Aged ; *Aging ; *Asian Continental Ancestry Group ; Humans ; Male ; Middle Aged ; *Nerve Fibers ; Reference Values ; Reproducibility of Results ; Retinal Ganglion Cells/*cytology ; Tomography, Optical Coherence/*methods ; Young Adult

PURPOSE: To evaluate the effect of the scanning laser ophthalmoscope (SLO) guided re-test mode on short- and long-term measurement variability of peripapillary retinal nerve fiber layer (RNFL) thickness obtained by spectral domain-SLO optical coherence tomography (SD-SLO/OCT). METHODS: Seventy five healthy eyes were scanned 3 times per day (intra-session variability) by both the SLO guided re-test mode and the independent mode of SD-SLO/OCT. Subjects were scanned 3 times by both modes at visits within a 2-week interval (inter-session variability). For testing longitudinal variability, 3 separate exams were performed over 6 months by both modes. The coefficient of variation (CV), reproducibility coefficient (RC) and intraclass correlation coefficient of RNFL thickness were compared between the two modes. RESULTS: The intra-session RC and CV ranged from 5.4 to 12.9 microns and 1.76% to 5.72% when measured by independent mode and 5.4 to 12.5 microns and 1.75% to 5.58% by re-test mode, respectively. The inter-session RC and CV ranged from 5.8 to 13.3 microns and 1.89% to 5.78% by independent mode and 5.8 to 12.7 microns and 1.90% to 5.54% by re-test mode, respectively. Intra-session and inter-session variability measurements were not significantly different between the two modes. The longitudinal RC and CV ranged from 8.5 to 19.2 microns and 2.79% to 7.08% by independent mode and 7.5 to 14.4 microns and 2.33% to 6.22% by re-test mode, respectively. Longitudinal measurement variability was significantly lower when measured by the re-test mode compared to the independent mode (average, p = 0.011). CONCLUSIONS: The SLO guided re-test mode for RNFL thickness measurement in SD-SLO/OCT employing a tracking system improved long-term reproducibility by reducing variability induced by inconsistent scan circle placement.
Adult ; Algorithms ; Anatomy, Cross-Sectional ; Female ; Humans ; Male ; Nerve Fibers ; Ophthalmoscopes ; Reference Values ; Reproducibility of Results ; Retinal Ganglion Cells/*cytology ; Tomography, Optical Coherence/*methods

OBJECTIVETo investigate in vivo survival of retinal ganglion cells (RGCs) after partial blockage of optic nerve (ON) axoplasmic flow by sub-retinal space or vitreous cavity injection of brain-derived neural factor (BDNF) produced by genetically modified neural progenitor cells (NPCs).

METHODSAdult Sprague-Dawley (SD) rat RGCs were labeled with granular blue (GB) applied to their main targets in the brain. Seven days later, the left ON was intra-obitally crushed with a 40 g power forceps to partially block ON axoplasmic flow. Animals were randomized to three groups. The left eye of each rat received a sham injection, NPCs injection or an injection of genetically modified neural progenitors producing BDNF (BDNF-NPCs). Seven, 15 and 30 days after ON crush, retinas were examined under a fluorescence microscope. By calculating and comparing the average RGCs densities and RGC apoptosis density, RGC survival was estimated and the neuro-protective effect of transplanted cells was evaluated.

RESULTSSeven, 15 and 30 days after crush, in the intra-vitreous injection group, mean RGC densities had decreased to 1885 +/- 68, 1562 +/- 20, 1380 +/- 7 and 1837 +/- 46, 1561 +/- 58, 1370 +/- 16, respectively with sham injection or neural progenitors injection. However, RGCs density in the groups treated with intra-vitreous injection of BDNF-NPC was 2101 +/- 15, 1809 +/- 19 and 1625 +/- 34. Similar results were found in groups after sub-retinal injection. Higher densities were observed in groups treated with BDNF-NPCs. There were statistically significant differences among groups through nonparametric tests followed by the Mann-Whitely test. RGC apoptosis density in BDNF-NPC at each follow-up time was less than in other groups.

CONCLUSIONSA continuous supply of neurotrophic factors by the injection of genetically modified neural progenitors presents a highly effective approach to counteract optic neuropathy and RGC degeneration after partial ON axoplasmic flow blockage.

Animals ; Apoptosis ; Axonal Transport ; Brain-Derived Neurotrophic Factor ; genetics ; Cell Survival ; Gene Transfer Techniques ; Genetic Therapy ; Glaucoma ; therapy ; Male ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells ; cytology ; Stem Cells ; physiology ; Vitreous Body ; metabolism

PURPOSE: To assess the reproducibility of circumpapillary retinal nerve fiber layer (cpRNFL) thickness measurement (measurement agreement) and its color-coded classification (classification agreement) by Cirrus spectral domain optical coherence tomography (OCT) in pseudophakic eyes. METHODS: Two-hundred five participants having glaucoma or glaucoma suspected eyes underwent two repeated Cirrus OCT scans to measure cpRNFL thickness (optic disc cube 200 x 200). After classifying participants into three different groups according to their lens status (clear media, cataract, and pseudophakic), values of intra-class coefficient (ICC), coefficient of variance, and test-retest variability were compared between groups for average retinal nerve fiber layer (RNFL) thicknesses and that corresponding to four quadrant maps. Linear weighted kappa coefficients were calculated as indicators of agreement of color code classification in each group. RESULTS: ICC values were all excellent (generally defined as 0.75 to 1.00) for the average and quadrant RNFL thicknesses in all three groups. ICC values of the clear media group tended to be higher than those in the cataract and pseudophakic groups for all quadrants and average thickness. Especially in the superior and nasal quadrants, the ICC value of the cataract group was significantly lower than that of the clear media and pseudophakic groups. For average RNFL thickness, classification agreement (kappa) in three groups did not show a statistically significant difference. For quadrant maps, classification agreement (kappa) in the clear media group was higher than those in the other two groups. CONCLUSIONS: Agreement of cpRNFL measurement and its color code classification between two repeated Cirrus OCT scans in pseudophakic eyes was as good as that in eyes with clear crystalline lens. More studies are required to ascertain the effect of lens status on the reproducibility of Cirrus OCT according to different stages of glaucoma patients.
Aged ; Cataract/complications ; Cataract Extraction ; Female ; Glaucoma/complications/*pathology ; Humans ; Lens, Crystalline/cytology/pathology ; Male ; Middle Aged ; Nerve Fibers/pathology ; Optic Disk/pathology ; Pseudophakia/complications ; Reproducibility of Results ; Retinal Ganglion Cells/*pathology ; Tomography, Optical Coherence/*methods/*standards

One common feature of glaucoma, optic neuritis and some other optic nerve diseases is sustained and irreversible apoptosis of retinal ganglion cells (RGCs). Ginkgolide B is believed to protect neurons in brain and contribute to neurite outgrowth and synapse formation. The aim of the present study was to explore the effects of Ginkgo biloba extract (EGB761) and ginkgolide B on axonal growth of RCGs. Retina explants were cultured in three-dimensional tissue culture system, and the number and length of neurites were analyzed. Immunohistochemistry staining was performed to confirm that the neurite observed was axon of RGCs. TUNEL and activated caspase-3 staining were also applied to observe RGCs apoptosis. The result shows that neurites of RGCs treated with EGB761 or ginkgolide B were more and longer than those in control. The neurite is proved to be the axon of RGCs by immunostaining. Furthermore, compared with control group, RGCs treated with ginkgolide B showed decreased cellular apoptosis and inhibited caspase-3 activation. These results suggest ginkgolide B can promote RGCs axon growth by protecting RGCs against apoptosis.
Animals ; Apoptosis ; Axons ; drug effects ; Caspase 3 ; metabolism ; Ginkgolides ; pharmacology ; Lactones ; pharmacology ; Neurites ; drug effects ; Organ Culture Techniques ; Plant Extracts ; pharmacology ; Rats ; Retina ; Retinal Ganglion Cells ; cytology ; drug effects

BACKGROUNDNeural apoptosis is generally believed to be mediated by two distinct pathways, caspase-dependant and caspase-independent pathways. This study investigated the apoptotic pathways involved in retinal ganglion cells in acute diabetes in rats.

METHODSDiabetes was induced in male Wistar rats by a peritoneal injection of streptozotocin (STZ). Expression and localization of caspase-3 and apoptosis-inducing factor (AIF) proteins in the retina of diabetic rats was examined by Western blotting and immunohistochemistry analyses. Terminal transferase dUTP nick end labeling (TUNEL) assay and immunofluorescent staining specific for caspase-3 and AIF were applied to analyze for apoptosis of retinal ganglion cells. In addition, a caspase-3 inhibitor DEVD-CHO was injected intravitreally to further determine the apoptotic pathways of retinal ganglion cells triggered in acute diabetes.

RESULTSTwo weeks after induction of diabetes, a significant increase in caspase-3 protein expression and localization occurred in the nerve fiber layer, ganglion cell layer, and inner plexiform layer of the retina. Four weeks after the onset of diabetes, the increase in caspase-3 expression was profound eight weeks postinduction of diabetes (P < 0.05). Meanwhile, no AIF protein expression was detected in this study. In addition, intravitreal administration of the caspase-3 inhibitor DEVD-CHO reduced apoptosis of retinal ganglion cells by its direct inhibitory action on caspase-3.

CONCLUSIONCaspase-dependent apoptotic pathways may be the main stimulant of STZ-induced retinal ganglion cell apoptosis in acute diabetes.

Animals ; Apoptosis ; drug effects ; physiology ; Apoptosis Inducing Factor ; metabolism ; Blood Glucose ; metabolism ; Blotting, Western ; Body Weight ; Caspase 3 ; metabolism ; Caspase Inhibitors ; Caspases ; metabolism ; Diabetes Mellitus, Experimental ; In Situ Nick-End Labeling ; Male ; Oligopeptides ; administration & dosage ; pharmacology ; Rats ; Rats, Wistar ; Retina ; metabolism ; Retinal Ganglion Cells ; cytology ; metabolism