Inhibition of miR-29a-3p Alleviates Apoptosis of Lens Epithelial Cells via Upregulation of CAND1.

PURPOSE: Accumulated evidence has shown that microRNAs (miRNAs) are closely related to the pathogenesis and progression of senile cataracts. Here we investigate the effect of miR-29a-3p in cataractogenesis and determined the potential molecular mechanism involved. METHODS: In this study, we constructed a selenite cataract model in rats and obtained the miRNAs related to cataracts by whole transcriptome sequencing. To investigate the effect and mechanism of miR-29a-3p on cataracts, we performed several in vivo and in vitro experiments, including CCK8 assay, flow cytometry, luciferase reporter assay, Edu assay, and western blot analysis. RESULT: Sequencing data showed downregulation of miR-29a-3p in rats with selenite cataracts. Down-regulation of miR-29a-3p could promote lens epithelial cells (SRA01/04) proliferation and inhibit cell apoptosis, and miR-29a-3p silence could inhibit the development of cataracts. Additionally, CAND1 was a direct target gene for miR-29a-3p. CONCLUSION: These data demonstrate that miR-29a-3p inhibits apoptosis of lens epithelial cells by regulating CAND1, which may be a potential target for senile cataracts.

Changes in tumor suppressors and inflammatory responses during hydrogen peroxide-induced senescence in rat fibroblasts.

Cell proliferation and senescence are processes induced by oxidative stress. In this study, we aimed to establish a cellular model of rapid proliferation and senescence of rat tail-tip fibroblasts by hydrogen peroxide (H2O2), a well-known oxidant. On this basis, changes in oxidative stress, inflammatory response and cell cycle of fibroblasts were studied. After H2O2 treatment, cell counting and flow cytometry results showed that 50 µM of H2O2 for 12 h and 100 µM for 8 h effectively promoted fibroblast proliferation, while 500 µM rapidly led to cell cycle arrest. In addition, stimulation with H2O2 at a concentration of 50 µM also promoted the inflammatory effects of the cells. At a concentration of 100 µM H2O2, the cellular antioxidant system began to collapse at 8 h and began to affect cellular activity. 500 µM of H2O2 at 4 h the levels of senescence-associated ß-galactosidase, a marker of senescence and oxidative stress, were almost positive in fibroblasts. In addition, we found that the risk of fibroblasts carcinogenesis increased with increased H2O2 stimulation. The results of this study indicate that H2O2 can cause rapid proliferation and senescence of fibroblasts and that its mechanism of action may be mainly through influencing cellular antioxidant systems, cellular inflammatory responses and cell cycle.

Comparison of the accuracy of intraocular lens power calculation formulas for eyes after corneal refractive surgery.

BACKGROUND: In cataract surgery, calculating intraocular lens (IOL) power in patients who have previously received corneal refractive surgery on the same eye presents a clinical challenge. This study aims to compare the accuracy of the Haigis-L, Barrett True-K, and Shammas-PL formulas in predicting the IOL power in eyes following corneal refractive surgery. METHODS: This study analyzed 32 eyes belonging to 28 patients who underwent cataract surgery and IOL implantation after previously undergoing myopic corneal refractive surgery. The IOL power was calculated using the Haigis-L, Barrett True-K, and Shammas-PL formulas, and the accuracy of the three formulas was compared. RESULTS: The Haigis-L, Barrett True-K, and Shammas-PL formulas had a mean arithmetic IOL prediction error of -0.65, -0.39, and -0.46, respectively. The mean numerical errors of the three formulas were significantly different from zero (P<0.001). The smallest median absolute refraction prediction error (median =0.40) belonged to the Barrett True-K formula, which was significantly smaller than that of the Haigis-L formula (median =0.57, P<0.05) but similar to that of the Shammas-PL formula (median =0.49, P>0.05). There was no significant difference in the percentage of eyes within either ±0.50 D or ±1.00 D of the predicted refraction error across the three formulas. CONCLUSIONS: The Barrett True-K formula can predict IOL power in eyes that have previously undergone myopic corneal refractive surgery better than the Haigis-L formula.

[The new method of cells growing on the glass slide].

AIM: To improve the method of cell growing on the glass slide. METHODS: Cells were planted in a system making by 1 ml tips and slide. RESULTS: Cells grow on the slide directly , no pollution and well proliferation, was fewer dropped off the slide than the traditionary method. CONCLUSION: The improved method had the advantages including easy-material, low-price, well-effect and convenient-operation , and prior to the traditionary method.

[A study on the relationship between the expression of apoptosis-related gene and the injury time in earlier period following cerebral contusion].

OBJECTIVE: To investigate the relationship between the expressive variety of apoptosis-related gene Bcl-2, Fas and the brain injury time during earlier period after cerebral contusion. METHODS: The morphologia feature of brain tissue was observed under microscopy and immunohistochemistry, image analyze technique was applied to detected the expression of Bcl-2 and Fas. RESULTS: Typical apoptotic cells were seen 8 hours after cerebral contusion. The expression of apoptosis-related gene was noted after 30 minutes and keep increase subsequently. The expression of Bcl-2 reached maximum level at 4 hours after brain trauma and then declined. CONCLUSION: Detecting the expression of Bcl-2 and Fas would be of valuable in the distinguishment of promortem and postmortem injury, and the estimation of brain injury time during the earlier period after cerebral contusion.