Short-wavelength blue light contributes to the pyroptosis of human lens epithelial cells (hLECs).

PURPOSE: The purpose of this study is to examine the effect of short-wavelength blue light (SWBL) on cultured human lens epithelial cells (hLECs). The pathogenesis of cataracts after SWBL exposure is discussed. METHODS: HLE-B3 hLECs were randomly divided into 3 groups: the NC group, which was grown in a dark incubator; the acetyl (Ac)-Tyr-Val-Ala-Asp-chloromethyl ketone (AC-YVAD-CMK) treatment group; and the SWBL exposure group. After SWBL (2500 lux) irradiation (for 8, 16, 24, and 32 h), caspase-1 and gasdermin D (GSDMD) expression levels in HLE-B3 hLECs were examined using ELISA, immunofluorescence staining, and Western blotting analyses. Double-positive staining of hLECs for activated and inhibited caspase-1 was used to determine pyroptosis in HLE-B3 hLECs. RESULTS: SWBL led to hLEC death, but a caspase-1 inhibitor suppressed cell death. The flow cytometry results also confirmed the dose-dependent effect of SWBL irradiation on the pyroptotic death of hLECs. Caspase-1 and GSDMD expression levels in all hLEC groups changed with blue light exposure times (8, 16, 24, and 32 h) and were higher in the AC-YVAD-CMK and SWBL exposure groups than in the NC group. The immunofluorescence results revealed higher GSDMD-N expression in the cell membrane of both the AC-YVAD-CMK and SWBL exposure groups than in the NC group. CONCLUSIONS: Based on the data, SWBL induces pyroptotic programmed cell death by activating the GSDMD signalling axis in HLE-B3 hLECs. These results provide new insights into the exploitation of new candidates for the prevention of cataracts.

Radiotherapeutic implications of the updated ICRP thresholds for tissue reactions related to cataracts and circulatory diseases.

Radiation therapy of cancer patients involves a trade-off between a sufficient tumour dose for a high probability of local control and dose to organs at risk that is low enough to lead to a clinically acceptable probability of toxicity. The International Commission on Radiological Protection (ICRP) reviewed epidemiological evidence and provided updated estimates of 'practical' threshold doses for tissue injury, as defined at the level of 1% incidence, in ICRP Publication 118. Particular attention was paid to cataracts and circulatory diseases. ICRP recommended nominal absorbed dose threshold for these outcomes as low as 0.5 Gy. Threshold doses for tissue reactions can be reached in some patients during radiation therapy. Modern treatment planning systems do not account for such low doses accurately, and doses to therapy patients from associated imaging procedures are not generally accounted for. While local control is paramount, the observations of ICRP Publication 118 suggest that radiation therapy plans and processes should be examined with particular care. The research needs are discussed in this paper.

Ultraviolet B Radiation Stimulates the Interaction between Nuclear Factor of Activated T Cells 5 (NFAT5) and Nuclear Factor-Kappa B (NF-κB) in Human Lens Epithelial Cells.

PURPOSE: Nuclear factor-kappa B (NF-κB) has been proposed as a therapeutic target for the treatment of cataracts. The authors investigated the relationship between nuclear factor of activated T cells 5 (NFAT5) and NF-κB in ultraviolet B (UVB)-irradiated human lens epithelial (HLE) cells. METHODS: Human lens epithelial B-3 (HLE-B3) cells were exposed to UVB light at a dose of 10 mJ/cm2 and then incubated for 24 h. Cell viability was assessed by using the Cell Counting Kit-8 (CCK-8) assay. Gene expression level of NFAT5 was determined using real-time quantitative polymerase chain reaction (qPCR). Protein expression levels of NFAT5, NF-κB p65, and α-smooth muscle actin (α-SMA) and the association of NFAT5 with the NF-κB p65 subunit were measured by Western blot analysis and a co-immunoprecipitation assay, respectively. The cellular distribution of NFAT5 and NF-κB p65 was examined by triple immunofluorescence staining. RESULTS: At 24 h after UVB exposure, cell viability significantly decreased in a dose-dependent manner, and UVB light (15 and 20 mJ/cm2) significantly increased the ROS generation. UVB irradiation increased NFAT5 mRNA and protein levels and increased phosphorylation of NF-κB in HLE-B3 cells. α-SMA protein levels were increased in the irradiated cells. In addition, NFAT5 and NF-κB translocated from the cytoplasm to the nucleus, and binding between the p65 subunit and NFAT5 was increased. CONCLUSIONS: Exposure to UVB radiation induces nuclear translocation and stimulates binding between NFAT5 and NF-κB proteins in HLE-B3 cells. These interactions may form part of the biochemical mechanism of cataractogenesis in UVB-irradiated HLECs.

[Treatment of senile cataracts at initial and immature stages in the ophthalmic department of Piket Sanatorium]. / Lechenie senil'nykh katarakt nachal'noi i nezreloi stadii v glaznom otdelenii sanatoriia "Piket".

Five-minute ultrasonic exposure of 0.4 Wt/cm2 intensity and 880 kHz frequency at acoustic contact through isotonic NaCl solution in the permanent mode (10-15 sessions) in combination with exposure to sinusoidal alternating 50-period magnetic field for up to 20 min had a positive stable therapeutic effect in patients with initial and immature senile cataracts, decelerating the processes of maturing. A course of treatment consisted of regular annual therapy according to the above protocol. The best results were attained in the group treated at the sanatorium and administered a course of complex spa therapy; this is one more confirmation that senile cataract is a dysfunction of the ageing organism suffering from many diseases requiring total-systems treatment in addition to the treatment for cataract.

[Laser irradiation: study of total effect of irradiation of the eyeball. A clinical study]. / Lazernoe izluchenie: issledovanie obshchego deistviia pri obluchenii glaznogo bloka. Klinicheskoe issledovanie.

Lipid peroxidation products, antioxidant system parameters, somatotrophic hormone, corticosteroids, fibronectin, and cyclic nucleotides were measured in the blood of 119 patients with open-angle glaucoma and mature senile cataract before and after a course of exposure of the eyeball to He-Ne laser. Statistically significant changes in the examined parameters were revealed, explaining to a great measure the antiinflammatory and vasodilating effects of laser and its ability to intensify the repair processes.

[Measurement of ocular lens ionizing radiation exposure after radioiodine therapy]. / Bestimmung der Augenlinsenexposition bei Patienten nach einer Radioiodtherapie.

AIM: Current reports for the radiation cataracts contained a warning for deterministic effects at 1-2 Gy radiation single exposure for lens. Recently, the German Radiation Protection Board (SSK) published a document (234. SSK-Board) in that threshold dose for radiation cataracts is claimed at 0.5 Gy. The lens of the eye is recognized as one of the most radiosensitive tissues in the human body, and the International Commission on Radiological Protection (ICRP 103) has defined a limit of 150 mSv for its exposure.Recently, the ICRP lowered this limit down to 20 mSv per year.However, this limit does not apply to patients. Therefore, the question of the lens radiation exposure for patients underwent a radioiodine therapy (RIT) is a point at issue. PATIENTS, METHODS: A total of 41 patients (age: 22-92 years) underwent a radioiodine therapy were included in the study. Optical stimulated luminescence dosimeters were used to measure the radiation exposure. The dosimeters were fastened nearby the patient's eye lens. The measurement was carried out up to 48 h after radioiodine application and the patients were divided into three groups. Group 1: patients underwent a diagnostic 131I whole body scan (mean activity: 370 MBq); group 2: thyriod carcinoma patients under RIT (mean activity: 3700 MBq); group 3: hyperthyroid patients under RIT (activity: 180-1237 MBq). RESULTS: The cumulative exposure of the eye lens during the stay at the therapy unit (48 h) was 4.8 ± 0.7 mGy in group 1, 24.5-50.5 mGy in group 2 and 2.7-26.3 mGy in group 3, respectively. For the calculation of the expected cumulative dose, including follow-up after patient's dismissal, the effective half-lives were involved. The cumulative doses were obtained to be 6 ± 1 mGy in the first group, 63 ± 15 mGy in the second and 5-148 mGy in the third. CONCLUSION: The results show that there exists a low risk for radiation cataract in a nuclear medicine therapy unit. After serial radioiodine therapies radiation-induced lens opacity cannot be expected.

Fototoxicidad. Radiaciones ultravioleta y cataratas / Phototoxicity. Ultraviolet radiation and cataracts

No disponible

Antioxidants and cataract: (cataract induction in space environment and application to terrestrial aging cataract).

The effect of several antioxidants and cysteine-elevating precursor drugs (prodrugs) was tested on lens damage occurring after in vitro exposure to low levels of 60Co-gamma-irradiation, to simulate in vitro the exposure to radiation in vivo of (1) astronauts (2) jet crews (3) military radiation accident personnel. Tocopherol (100 microM), ascorbic acid (1 mM), R-alpha-lipoic acid (1 mM), and taurine (0.5 mM) protected against radiation-associated protein leakage. MTCA and ribocysteine protected lenses against opacification, LDH and protein leakage, indicating that antioxidants and prodrugs of cysteine appear to offer protection against lens damage caused by low level radiation.