Structural Characteristics of the Lens in Presenile Cataract

The purpose of this work is to examine the structure of the anterior lens epithelial cells (aLECs) of presenile idiopathic cortical cataract to investigate the possible structural reasons for its development. The anterior lens capsules (aLCs: basement membrane and associated lens epithelial cells) were obtained from routine uneventful cataract surgery of 5 presenile cataract patients (16 and 41 years old women and 29, 39, and 45 years old men). None of the patients had family history of cataract, medication, or trauma and they were otherwise healthy. In addition, the patients did not have any other abnormal features in the ocular status except cataract. The aLCs were prepared for scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The most prominent abnormal features observed by SEM for all 5 studied presenile cataract patients were the changes of the aLECs structure with the dents, the selective concavity of some LECs, at their apical side centrally toward the nucleus. In addition, TEM showed the thinning of the lens epithelium with the segmentally concave cells and the compressed and elongated nuclei. Abnormal and distinguishable structural features were observed in the anterior lens epithelium aLECs in all 5 patients with presenile cataract. Disturbed structure of aLECs, regularly present in presenile cataract type is shown that might be associated with water accumulation in the presenile idiopathic cortical cataract lens.

Enhancement of Amyloid β1–43 Production in the Lens Epithelium of Japanese Type 2 Diabetic Patients

We investigated whether the accumulation of amyloid β-protein (Aβ) is enhanced in the lenses of diabetic patients. Lens epithelium samples were collected from Japanese patients during cataract surgery, and the Aβ levels and gene expression of Aβ-producing and -degrading enzymes in the samples were measured by ELISA and real-time RT-PCR, respectively. The Aβ1–43 levels in lenses of non-diabetic patients were low (0.11 pmol/g protein), while the levels in lenses of diabetic patients were significantly (6-fold) higher. Moreover, the Aβ1–43/total-Aβ ratio in the lenses of diabetic patients was also significantly higher than non-diabetic patients (p < 0.05). In addition, the mRNA levels for Aβ-producing enzymes were also enhanced in the lenses of diabetic patients. In contrast to the results for Aβ-producing enzymes, the mRNAs for the Aβ-degrading enzymes in the lenses of diabetic patients were significantly lower than in non-diabetic patients (p < 0.05). Furthermore, Aβ1–43/total-Aβ ratio in lenses was found to increase with plasma glucose level. In conclusion, these results suggest that high glucose levels cause both an increase in Aβ production and a decrease in Aβ degradation, and these changes lead to the enhancement in Aβ1–43 accumulation in the lenses of diabetic patients. These findings are useful for developing therapies for diabetic cataracts and for developing anti-cataract drugs.

Transfection of CTGF siRNA inhibits transdifferentiation in human lens epithelium cell line B3 in vitro

AIM: To investigate the expression of connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA) in human lens epithelium cell (HLEC) line B3 after transfection by liposome-coated small interfering RNA (siRNA) targeting CTGF. METHODS: HLECs were transfected with siRNA targeting CTGF, labeled with 5’-fluorescein isothiocyanate (5’-FITC) and coated with lipofectamine. The transfection ratio was evaluated via fluorescence intensity. Cell counting kit-8 (CCK-8) assay was performed to assess cytoviability of both non-transfected and transfected HLECs. Quantitative reverse transcription-polymerase chain reaction (RT-PCR), cell immunochemistry and Western blot analysis were conducted to detect the expression changes of CTGF and α-SMA after transfection. RESULTS: A highly effective transfection ratio was observed in siRNA co-transfected with lipofectamine. The transfection ratio reached 95% at 24h. The proliferation of HLECs was inhibited by siRNA after 72h transfection. The expression of CTGF and α-SMA significantly decreased in HLECs after transfected by CTGF siRNA for 24h. This effect was not found in negative control siRNA. CONCLUSION: siRNA targeting CTGF decrease CTGF and α-SMA expression in HLECs, which is a potential therapeutic strategy for posterior capsular opacification.