| 1. |
- Andersson, Madeleine, et al.
(författare)
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Caspase and proteasome activity during staurosporin-induced apoptosis in lens epithelial cells
- 2000
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404. ; 41:9, s. 2623-32
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To determine what caspases are activated during staurosporin-induced apoptosis in cultured bovine lens epithelial cells (BLECs), to study the time course of caspase activation in relation to morphologic changes, and to investigate the effect of caspase and/or proteasome inhibition on apoptosis. METHODS: BLECs were incubated with staurosporin at different concentrations or for different times. Phosphatidylserine (PS) externalization was detected by annexin-V labeling, nuclear morphology was studied by staining with Hoechst 33342 stain (Hoechst, Frankfurt, Germany), and the percentage of apoptotic cells was determined by the TdT-dUTP terminal nick-end labeling (TUNEL) assay. The activity of caspase-1, -2, -3, -4, -8, and -9 as well as the chymotrypsin-like activity of the proteasome was measured by the use of fluorogenic peptide substrates. Inhibition of the proteasome was performed by incubation with 10 microM lactacystin, and caspases were inhibited by 1 microM Z-DEVD-FMK or 20 microM Z-VAD-FMK. RESULTS: Staurosporin treatment caused a dose- and time-dependent increase in the number of apoptotic cells and in caspase-3 activity. Activation of caspase-2, -4, -8, and -9 was also seen. Caspase activity was increased after 3 hours' incubation with 1 microM staurosporin, which is also the time when most cells became annexin-V-positive. Nuclear changes indicative of apoptosis, viewed with both Hoechst and TUNEL staining, appeared after 4 to 6 hours of staurosporin incubation. Incubation of BLECs with lactacystin caused reduction of proteasome activity and increased apoptosis, evidenced in both the TUNEL assay and caspase-3 activation. Preincubation of lens epithelial cells with caspase inhibitors caused complete inhibition of lactacystin- or staurosporin-induced caspase-3 activation (Z-DEVD-FMK/Z-VAD-FMK) and also of caspase-2, -4, -8, and -9 (Z-VAD-FMK), but the reduction in TUNEL-positive cells was only partial. PS translocation and DNA fragmentation after staurosporin treatment occurred despite complete caspase blockade. CONCLUSIONS: Staurosporin-induced apoptosis in BLECs involves activation of several caspases. Inhibition of the proteasome causes caspase-3 activation and apoptosis. Both staurosporin- and lactacystin-induced apoptosis can be executed in a caspase-independent manner. The present data are useful for understanding of proteolytic mechanisms during apoptosis in lens epithelial cells, which may be an important event in normal lens development as well as in some types of cataract.
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| 2. |
- Andersson, Madeleine, et al.
(författare)
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Decreased caspase-3 activity in human lens epithelium from posterior subcapsular cataracts
- 2003
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Ingår i: Experimental Eye Research. - 0014-4835. ; 76:2, s. 175-82
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Tidskriftsartikel (refereegranskat)abstract
- Apoptosis has been implied in normal lens development in the embryo as well as in lens fibre differentiation. It has also been suggested to play a role in non-congenital cataract and in the formation of posterior subcapsular opacification, but data on the presence of apoptosis in human lens epithelium from cataractous lenses are scarce and conflicting. The present study aimed to investigate apoptosis in lens epithelium from patients undergoing cataract surgery. The amount of apoptosis detected was correlated to age, gender, type of cataract, medications and disease. Moreover, the ability of human lens epithelial cells in culture to respond to the apoptosis-inducing agent staurosporin by activation of caspase-3 was investigated. Human lens capsulotomy specimens were collected immediately after surgery, frozen and later analysed with respect to caspase-3 activity, using the fluorogenic substrate Ac-DEVD-AMC. Generally, the activity of caspase-3 detected in this manner was very low and in 23% of the specimens it was non-detectable. However, there were differences in caspase activity between lens epithelial cells from different types of cataract, where samples from lenses with posterior subcapsular cataract exhibited significantly lower caspase-3 activity than lenses with a clear subcapsular zone. Age, gender or medications did not show any correlation with caspase activity but human capsulotomy specimens from diabetic patients exhibited significantly lower caspase-3 activity. Staurosporin caused a concentration-dependent increase in caspase activity in cultured human lens epithelial cells and the amount of apoptotic nuclei was also increased as viewed by staining with Hoechst 33342, showing chromatin condensation and nuclear fragmentation. Similar results were obtained when fresh human lens capsulotomy specimens were exposed to 1000 nM staurosporin for 24 hr. To conclude, the present data indicate that human lens epithelial cells have the ability to respond to apoptosis-inducing agents with caspase-3 dependent apoptosis, and that even though the general level of apoptosis in human lens epithelium in vivo is low, there are differences in caspase-3 activity levels in lenses with or without posterior subcapsular cataract. The latter finding supports previous studies indicating that this type of cataract may result from defective differentiation, in which apoptosis may play an important role.
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| 3. |
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| 4. |
- Bergman, Birgitta, 1941, et al.
(författare)
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Ocular changes, risk markers for eye disorders and effects of cataract surgery in elderly people: a study of an urban Swedish population followed from 70-97 years of age
- 2004
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Ingår i: Acta Ophthalmologica Scandinavica. - : Wiley. - 1395-3907. ; 82, s. 166-74
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Tidskriftsartikel (refereegranskat)abstract
- Aims: To investigate the prevalence of and potential risk factors for ocular disorders and the effects of timing of cataract surgery from age 70–97 years. Population: A representative population sample taken from within the Gerontological and Geriatric Population Studies (H 70) in Gothenburg, Sweden (n = 958). All subjects underwent eye examinations at age 70 years in 1971 and subsequently at ages 82, 88, 95 and 97 years. All inhabitants of Gothenburg aged 95 and 97 years were invited to participate in the study. Results: Decreased vision (visual acuity ≤ 0.5) was found in 20% and 80% of subjects at ages 82 and 97 years, respectively. Blood folate and physical activity at age 70 years correlated positively and body mass index (BMI) negatively to visual acuity (VA) ≥ 0.8 at ages 82 and 88 years. Smoking at age 70 years correlated to early age-related maculopathy (ARM). Cataract surgery had been performed in 40% of subjects at age 97 years. Surgery 2 years earlier led to a 15% increase in time spent with improved vision. Conclusions: The deterioration of vision in elderly people is a major health problem, for which ‘low’ folate status, smoking, ‘high’ BMI and low physical activity are potential risk factors. Early cataract surgery is also beneficial in very old patients.
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| 5. |
- Brunnström, Gunilla, 2000, et al.
(författare)
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Quality of light and quality of life - the effect of lighting adaptation among people with low vision
- 2004
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Ingår i: Ophthal Physiol Opt. - : Wiley. - 0275-5408. ; 24, s. 274-280
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The study has investigated the effect of lighting on the daily activities (ADL) of the visually impaired in their homes by comparison before and after light adjustments were made in the kitchen, hall and bathroom. It has also investigated the additional effects on the quality of life after providing task lighting in the living room. METHOD: A total of 56 people were consecutively recruited from those receiving lighting adaptation help by the Low Vision Clinic in Goteborg. Ten persons did not complete the study. After medical examinations, lighting standards and psychosocial factors were charted. After lighting improvements were carried out in the kitchen, hall and bathroom, the subjects were randomly divided into two groups, an intervention and a comparison group. The task lighting in the living room was also improved for those included in the intervention group. Follow-up interviews to determine ADL and quality of life were performed 6 months after lighting adaptation. RESULTS: A marked effect on quality of life of the lighting in the living room was found for the intervention group. The effect on ADL of the basic lighting adaptation in kitchen, hall and bathroom for both groups was significant for tasks carried out on the working surface in the kitchen. Other activities in the kitchen and in the bathroom tended to improve but changes were not significant. CONCLUSION: The results confirm that it is possible to increase quality of life by improving the lighting conditions.
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| 6. |
- Karlsson, Jan-Olof, 1944, et al.
(författare)
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Acute Effects of Indomethacin on Mitochondrial Function and Glutathione Levels in the Mouse Lens in Organ Culture
- 2003
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Ingår i: Invest. Ophthalmol. Vis. Sci.. ; 44:5
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Konferensbidrag (refereegranskat)abstract
- Purpose, Experiments were carried out to study the effects of indomethacin on markers for oxidative damage and mitochondrial function in the intact mouse lens. Methods, Mouse lenses were incubated with fluorogenic indicator dyes prior to administration of 50 {micro}M indomethacin. The response was monitored, in real time, for several hours. Mitochondrial depolarization was followed by preloading the lens with Rhodamine 123 (10 {micro}g/ml). Peroxide production was studied in lenses loaded with 50{micro}M DCF-DA and superoxide levels with 10 {micro}M hydroethidium. Glutathione levels were assayed with 50 {micro}M monochlorobimane following short-term administration of indomethacin. Results, No significant changes in the production of peroxide or superoxide were found up to 3 hours after administration of indomethacin. The level of reduced glutathione was reduced by approximately 10 percent 3 h after drug administration. There was a significant increase (20%) of mitochondrial depolarization, compared to control lenses, one hour following indomethacin administration. Conclusions, The frequent use of nonsteroidal anti-inflammatory drugs in ophthalmology necessitates a close examination of effects besides the anti-inflammatory ones. This study points to relatively rapid effects on mitochondrial function and glutathione levels in the cultured mouse lens. The possible relation between these changes and the development of cataract remains to be studied.
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| 7. |
- Karlsson, Jan-Olof, 1944, et al.
(författare)
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Inhibition Of Glycogen Synthase Kinase (gsk-3) Affects Markers Of Oxidative Stress And Attenuates Apoptosis In Human Lens Epithelial Cells
- 2004
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Ingår i: Invest. Ophthalmol. Vis. Sci.. ; 45:5
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Konferensbidrag (refereegranskat)abstract
- Purpose: GSK-3, an evolutionary conserved S/T kinase which regulates cell fate determination in diverse organisms have been implicated in the formation of amyloid b-peptides and the phosphorylation of tau and catenin. Inhibition of GSK-3 can be obtained via the structurally unrelated substances lithum or Kenpaullone. The lens and the lens epithelial cells are excellent models to study the role of this enzyme. Methods: Confluent human lens epithelial cells (HLEC) were exposed to the GSK-3 inhibitors lithium (2 mM) or Kenpaullone (2 {micro}M) for times upp to 24h. The cells were, before or after treatment, placed in medium containing fluorogenic indicators of oxidative damage. DCFH-DA was used to assay peroxides, mitochondrial function was evaluated with Rhodamine 123, monochlorobimane was used to assay intracellular glutathione (GSH) levels, Proteolytic activities were assayed, on line, with cell-permeable fluorogenic substrates.Proteasome and calpain activities were assayed with LLVY-AMC, Cathepsin B with RR-AMC or FR-AMC. Metalloproteases were assayed with AAF-AMC. Caspase-3, 8 and 9 were assayed in cell extracts with DEVD-, IETD- or LEHD-AMC, respectively. Results: The mitochondrial membrane potential and the level of GSH increased by 10% after treatment with Li or Kenpaullone for 24h. No change was observed for peroxide production. The basal (low) level of caspase-3 activity was decreased by 20%. No significant effects were found concerning caspase-8 or 9 activities. No effect was observed on the activity of calpain, the proteasome, metalloproteases and cathepsin D/E activity. Conclusions:Inhibition of GSK-3 may protect against oxidative damage and attenuate apoptosis in HLEC. No changes of the other major proteolytic systems in the cell were detected. These data may be important for the interpretation of Wnt signaling and cell growth in HLEC as well as for the formation of amyloid in the lens.
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| 8. |
- Magnusson, Gunilla, 1968, et al.
(författare)
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Changes in visual acuity from 4 to 12 years of age in children operated for bilateral congenital cataracts.
- 2002
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Ingår i: The British journal of ophthalmology. - 0007-1161. ; 86:12, s. 1385-9
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: To investigate the long term effects of age at surgery on the development of visual acuity (VA) by measuring VA from preschool age to puberty. Furthermore, to report the VA levels at 12 years of age in a geographically based cohort of operated congenital bilateral cataracts. METHODS: All children born in four western counties of Sweden between January 1980 and December 1993 who were diagnosed with congenital cataracts were included in a longitudinal prospective study. The monocular VA of the better eye in 38 subjects was analysed at 4, 7, 10, and 12 years of age, with 20 total and 18 partial cataracts. The mean follow up time was 9.3 years after surgery. RESULTS: The final value of VA was 0.4 or above for approximately 50% of the subjects at 12 years of age. Visual acuity improved to a considerable extent after school age, especially in children who underwent surgery between the ages of 7 weeks and 1 year. Results for partial cataracts were favourable compared to those for total cataracts, reaching a mean of approximately 0.5 at age 12. The mean VA in the group of total congenital cataracts operated on before 7 weeks of age achieved higher values of VA at 4 years of age compared to children with total cataracts operated on between 7 weeks and 1 year of age. However, no statistically significant difference in VA results among these groups could be proved. CONCLUSION: Visual acuity improves to a considerable extent after school age in children with delayed visual development caused by congenital cataracts. Surgery within 7 weeks results in a more rapid development of VA, initially.
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| 9. |
- Magnusson, Gunilla, 1968, et al.
(författare)
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Evaluation of screening procedures for congenital cataracts.
- 2003
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Ingår i: Acta paediatrica (Oslo, Norway : 1992). - : Wiley. - 0803-5253 .- 1651-2227. ; 92:12, s. 1468-73
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To evaluate the efficacy of two different Swedish screening procedures for early detection of congenital cataracts in comparison with no screening. METHODS: Children born between January 1992 and December 1998 in Swedish regions with an established eye-screening routine procedure, diagnosed with congenital cataract, and operated on before 1 y of age, were included in a retrospective study. Age at referral and age at time of the operation were compared between regions using different screening procedures: screening in the maternity wards (Region 1), at the well-baby clinics (Region 2) and one region without any screening (Region 3). RESULTS: Seventy-two children were included in the study. Concerning early diagnosis and surgery, Region 1 differed significantly from Regions 2 and 3, which were more similar and were combined for further analysis. The difference in detected cases was greatest at 21 d of age (55% vs 18%; p < 0.001), but persisted even at 100 d of age (78% vs 64%; p < 0.02). Region 1 screening resulted in more and earlier cases detected than the other two regions (22 vs 15 per 100,000 births). In 72% of all cases, surgery was performed in response to referrals from either the maternity wards (36%), or the well-baby clinics (36%). However, half of the cases from the well-baby clinics were detected too late, i.e. at > 100 d. CONCLUSION: Eye screening in the maternity ward is preferable to well-baby clinic screening and to no screening at all, since it leads to early detection. Screening should also be performed routinely at well-baby clinics within the period when successful treatment is possible.
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| 10. |
- Magnusson, Gunilla, 1968, et al.
(författare)
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Glaucoma following congenital cataract surgery: an 18-year longitudinal follow-up.
- 2000
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Ingår i: Acta ophthalmologica Scandinavica. - 1395-3907. ; 78:1, s. 65-70
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To report the occurrence of postoperative glaucoma and to evaluate risk factors. METHODS: Children born in four of the western counties of Sweden who were diagnosed with congenital cataracts formed a cohort (n=137). The following parameters were evaluated: age at cataract surgery; type of surgery; visual outcome; postoperative IOP; optic disc abnormalities; date of onset of the complication; number of reoperations, including treatment for secondary cataract; presence of systemic anomalies; microphthalmus; and eye-related anomalies. RESULTS: A diagnosis of glaucoma was recorded for 12% of the eyes. The mean follow-up time was 9.6 years. There is a relationship between surgery before the age of 10 days and development of glaucoma. Microphthalmus is an important risk factor as well. CONCLUSIONS: Despite modern surgical techniques the incidence of aphakic glaucoma is 10% or higher. No time-dependent increase in the incidence of late-onset glaucoma between the 1980s and the 1990s could be proven.
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