OBJECTIVETo study the effects of different dose microwave radiation on protein components of cultured rabbit lens, and analyze the mechanisms of lens injury caused by microwave radiation.

METHODSCultured rabbit lens were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.25, 0.50, 1.00, 2.00, 5.00 mW/cm(2) for 8 hours in vitro. The transparency of lens was observed. Changes of protein concentration were detected after different lens protein components were extracted, including water-soluble protein (WSP), urea soluble protein (USP), alkali soluble protein (ASP) and sonicated protein (SP). The influence of microwave radiation on WSP was analyzed using SDS-PAGE electrophoresis and coomassie-blue staining.

RESULTSTransparency of lens decreased after radiation. There was obvious opacification of lens cortex after 5.00 mW/cm(2) microwave radiation for 8 hours. After 1.00, 2.00 and 5.00 mW/cm(2) radiation, the percentage of WSP decreased while USP increased obviously. There was no change of ASP. The percentage of SP decreased when the power of microwave was 5.00 mW/cm(2). The low molecular weight protein of WSP decreased while high molecular weight protein increased after microwave radiation.

CONCLUSIONMicrowave radiation higher than 1.00 mW/cm(2) can affect the proportion of WSP and USP in cultured rabbit lens, and cause changes of lens transparency and refractive power, which leads to lens opacity.

Animals ; In Vitro Techniques ; Lens, Crystalline ; metabolism ; radiation effects ; Microwaves ; adverse effects ; Proteins ; metabolism ; Rabbits

alphaB-crystallin is the structural protein of vertebrate lens, which is widely expressed in non-lens tissue. As one of the heat shock protein family members, alphaB-crystallin possesses biological properties of molecular chaperones and anti-apoptotic effects. Multi-factor injuries, such as retinopathy, inflammation and nervous system diseases, have a closely relationship with alphaB-crystallin. This paper reviews the research progress of the expression and mechanism of alphaB-crystallin in retina and extraocular tissues and organs.
Crystallins ; Gene Expression Regulation, Developmental ; Heat-Shock Proteins/metabolism* ; Humans ; Lens, Crystalline ; Retina ; alpha-Crystallin B Chain/metabolism*

To investigate if the surface modification of intraocular lens (IOL) is efficient in the prevention of posterior capsular opacification (PCO), the acrylic surface of intraocular lens (Acrysof(R)) was polymerized with polyethylene glycol (PEG-IOL). The human lens epithelial cells (1x10(4) cells/mL) were inoculated on PEG grafted or unmodified acrylic lenses for the control. The adherent cells on each IOL surface were trypsinized and counted. The every PEG-IOL was implanted in 20 New Zealand rabbits after removal of crystalline lens. The formations of PCO were checked serially through retroilluminated digital photography, and the severity scores were calculated using POCOman(R). The cell adherence patterns on each IOL were examined by scanning electron microscopy. As a result, the mean number of adherent cells of PEG-IOL (3.2+/-1.1x10(3)) tended to be smaller than that of the acrylic controls (3.6+/-1.9x10(3)) without a statistical significance (p=0.73). However, the mean severity of PCO formation in PEG-IOL was significantly lower than that in the control during the third to sixth weeks after surgery. Scanning electron microscopy revealed that the more patch-like cells were found firmly attached to the IOL surface in control than in the PEG-IOL. Conclusively, PEG polymerization to the acrylic IOL would possibly lessen the formation of PCO after cataract removal.
Acrylic Resins/chemistry ; Biocompatible Materials ; Cataract/metabolism/*therapy ; Cell Adhesion ; Humans ; Lens Implantation, Intraocular/*methods ; Lens, Crystalline/cytology/ultrastructure ; Microscopy, Electron, Scanning ; Polyethylene Glycols/*chemistry/metabolism ; Time Factors

In order to investigate whether cultured normal human lens epithelial cells (LEC) express transforming growth factor beta (TGF-beta), reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical methods were used for detection of TGF-beta mRNA and protein in cultured normal human LEC. The results showed that a single RT-PCR amplified product about 310bp was obtained, and the sequence was homologous to the known sequence. TGF-beta immunostain was positive in the plasma of LEC. It was suggested that normal human LEC could produce TGF-beta, and LEC could be affected by TGF-beta through autocrine action.
Cells, Cultured ; Epithelial Cells/cytology ; Epithelial Cells/*metabolism ; Lens, Crystalline/cytology ; Lens, Crystalline/*metabolism ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics ; Transforming Growth Factor beta/*biosynthesis ; Transforming Growth Factor beta/genetics

We studied the nonenzymatic glycosylation of lens epithelial basement membranes (LEBM) of senile cataractous lenses of both diabetic and nondiabetic patients. The human LEBMs were isolated from surgically removed senile cataracts and purified by osmotic lysis and detergent treatments. Glycosylation assay of LEBMs was done using the colorimetric method of Fluckiger and Winterhalter. The glycosylation value ranged from 16.39 to 92.56 n mol/mg protein overall, with a mean of 63.54 +/- 24.56 n mol/mg protein for the diabetic specimens and a mean of 29.97 +/- 14.48 n mol/mg protein for the nondiabetic controls (P = 0.009). The study confirms our previous observation of in vivo glycosylation of the LEBM and further establishes that diabetic patients have a twofold increase in the amount of LEBM glycosylation when compared to their nondiabetic counterparts.
Aged ; Basement Membrane/metabolism ; Cataract/metabolism ; Diabetes Mellitus, Type 2/*metabolism ; Epithelium/metabolism ; Female ; Glucose/metabolism ; Glycosylation ; Humans ; Lens, Crystalline/*metabolism ; Male

We studied the nonenzymatic glycosylation of lens epithelial basement membranes (LEBM) of senile cataractous lenses of both diabetic and nondiabetic patients. The human LEBMs were isolated from surgically removed senile cataracts and purified by osmotic lysis and detergent treatments. Glycosylation assay of LEBMs was done using the colorimetric method of Fluckiger and Winterhalter. The glycosylation value ranged from 16.39 to 92.56 n mol/mg protein overall, with a mean of 63.54 +/- 24.56 n mol/mg protein for the diabetic specimens and a mean of 29.97 +/- 14.48 n mol/mg protein for the nondiabetic controls (P = 0.009). The study confirms our previous observation of in vivo glycosylation of the LEBM and further establishes that diabetic patients have a twofold increase in the amount of LEBM glycosylation when compared to their nondiabetic counterparts.
Aged ; Basement Membrane/metabolism ; Cataract/metabolism ; Diabetes Mellitus, Type 2/*metabolism ; Epithelium/metabolism ; Female ; Glucose/metabolism ; Glycosylation ; Humans ; Lens, Crystalline/*metabolism ; Male

OBJECTIVETo study the differences in expression of nuclear factor-kappaB (NF-kappaB) between human traumatic cataract and normal lenticular epithelial cells.

METHODSTotal RNA of anterior capsule specimens was taken under the microscope from normal cadaveric eyes donors and those suffering from traumatic cataract to make semi-quantitative RT-PCR and conduct analysis of differences in expression of NF-kappaB between them.

RESULTSAs compared with the mean of 0.8337 in normal control group, the expression equivalent of NF-kappaB was 0.9074 for the lenticular epithelial cells in traumatic cataract sufferers, and the differences are of noticeable significance (t = 2.447, P<0.05) accordingly.

CONCLUSIONSNF-kappaB is likely a kind of transcription factor necessary to maintain metabolism of normal lenticular epithelial cells. Higher NF-kappaB available in the traumatic cataract sufferer's lenticular epithelial cells means NF-kappaB is of possible relevance to occurrence and development of traumatic cataract.

Adolescent ; Adult ; Cataract ; genetics ; metabolism ; therapy ; Epithelial Cells ; metabolism ; Female ; Humans ; Lens, Crystalline ; injuries ; metabolism ; Male ; NF-kappa B ; genetics ; metabolism ; Polymerase Chain Reaction

OBJECTIVETo observe the effects of low power microwave radiation on lens hydration and lens epithelial cells in vitro, and detect the expression of PKC-alpha, c-fos and c-jun in lens epithelial cells.

METHODSRabbit lens were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.5, 2.0 and 5.0 mW/cm(2) in vitro. The hydration of lens was measured after 8 hours. Morphological changes of lens epithelial cells were observed using a phase-contrast microscope and Hoechst 33258 staining. Expression of PKC-alpha, c-fos and c-jun were analyzed using gel electrophoresis and western blot analysis.

RESULTSAfter 2.0 and 5.0 mW/cm(2) microwave radiation, the hydration of lens was increased compared to control groups (P<0.05), the shape of lens epithelial cells showed shrinking and disorder and cells nuclei appeared chromatin condensation. There was no change of lens and lens epithelial cells after 0.5 mW/cm(2) microwave radiation. The expression of PKC-alpha was significantly increased in cell membrane, however, decreased in cell cytoplasm after 2.0 mW/cm(2) microwave radiation for 2, 4, 6 and 8 hours. There was significantly increased expression of c-fos and c-jun protein compared with control groups (P<0.05, P<0.01).

CONCLUSIONLow power microwave radiation higher than 2.0 mW/cm(2) can activate PKC-alpha by increasing its expression in cell membrane, then induce high expression of c-fos and c-jun, which may relate to cellular signaling pathway of microwave radiation injury to lens and lens epithelial cells.

Animals ; Epithelial Cells ; metabolism ; pathology ; radiation effects ; In Vitro Techniques ; Lens, Crystalline ; metabolism ; pathology ; radiation effects ; Protein Kinase C-alpha ; metabolism ; Rabbits ; Transcription Factors ; metabolism

OBJECTIVETo compare the effects of different doses of microwave on the proliferative activity and cell cycle of cultured epithelial cells of rabbit lens, and to investigate the limit tolerant of microwave exposure.

METHODSCultured epithelial cells of rabbit lens were exposed to microwave radiation with frequency of 2,450 MHz and power density of 0.10, 0.25, 0.50, 1.00, 2.00 mW/cm(2) for 8 h in vitro. HE staining was used to observe the morphological changes of lens epithelial cells, the proliferative activity and cell cycle were measured by MTT assay and PI fluorescent staining.

RESULTS8 h after radiation, 0.50, 1.00 and 2.00 mW/cm(2) microwave could decrease the proliferation of lens epithelial cells, make the cells disordered arrangement, shrinkage, detachment, and inhibit the synthesis of cell DNA. The percentage of G(0)/G(1) phase cells were 71.95% +/- 2.12%, 75.68% +/- 3.35% and 82.40% +/- 8.68% respectively, which were higher than that in control group (61.68% +/- 5.76%, P < 0.05 or P < 0.01). The percentage of S phase cells were 19.32% +/- 3.07%, 16.08% +/- 4.91% and 12.98% +/- 8.08% respectively, which were lower than that in control group (28.05% +/- 5.12%, P < 0.05 or P < 0.01). No obvious changes could be detected in 0.10, 0.25 mW/cm(2) microwave groups (P > 0.05).

CONCLUSIONMicrowave exceeding 0.50 mW/cm(2) may make injury to lens epithelial cells after 8 hour radiation, which may be related to the effect of microwave radiation on cell cycle.

Animals ; Cell Cycle ; radiation effects ; Cells, Cultured ; DNA ; metabolism ; Epithelial Cells ; cytology ; metabolism ; radiation effects ; Lens, Crystalline ; cytology ; metabolism ; radiation effects ; Microwaves ; Rabbits

OBJECTIVETo investigate the effect of long-term power frequency electromagnetic field (50 Hz) exposure on the proliferation and apoptosis of human lens epithelial cells (SRA01/04 cells).

METHODSSRA01/04 cells in the exponential growth phase were exposed or sham-exposed to power frequency electromagnetic field (50 Hz, 2.3 mT) for 2 hours per day, 5 days every week. After 11 weeks of exposure, the cells were collected; the cell morphology was observed under a microscope, the cell viability was measured by MTT assay, the cell cycle and apoptosis were examined by flow cytometry, and the protein expression levels of cyclin D and proliferating cell nuclear antigen (PCNA) were determined by western blot.

RESULTSCompared with the sham-exposed SRA01/04 cells, most exposed cells became rounded and more stereoscopic, and heterochromatin gathered near the nuclear membrane in some exposed cells. The MTT assay showed that the viability of exposed cells was significantly increased compared with that of the sham-exposed cells (P < 0.05). Long-term power frequency electromagnetic field exposure led to significantly increased number of cells in S phase (P < 0.05), and the proliferation index was significantly higher in the exposed cells than in the sham-exposed cells (P < 0.05). There was no significant difference in apoptotic rate between the exposed cells and sham-exposed cells (P > 0.05). The exposed cells had significantly higher protein expression levels of cyclin D and PCNA than the sham-exposed cells (P < 0.05).

CONCLUSIONLong-term power frequency electromagnetic field exposure can promote cellular proliferation and change cell cycle in SRA01/04 cells, but it has no marked effect on the apoptosis of SRA01/04 cells.

Apoptosis ; Cell Line ; Cell Proliferation ; Cyclin D1 ; metabolism ; Electromagnetic Fields ; adverse effects ; Environmental Exposure ; adverse effects ; Epithelial Cells ; cytology ; Humans ; Lens, Crystalline ; cytology ; Proliferating Cell Nuclear Antigen ; metabolism