miR-211 promotes lens epithelial cells apoptosis by targeting silent mating-type information regulation 2 homolog 1 in age-related cataracts

AIM： To detect the expression of miR-211 in age-related cataract tissue, explore the effects of miR-211 on lens epithelial cell proliferation and apoptosis, and identify its target gene.METHODS： This study used real-time quantitative polymerase chain reaction（RT-q PCR） to measure the expression of miR-211 and its predicted target gene [silent matingtype information regulation 2 homolog 1（SIRT1）] in 46 anterior lens capsules collected from age-related cataract patients. Human lens epithelial cell line（SRA01/04） cells were transfected with either miR-211 mimics, mimic controls, miR-211 inhibitors or inhibitor controls, 72 h after transfection, miR NA and protein expression of SIRT1 were measured using RT-qP CR and Western blotting; then cells were exposed to 200 μmol/L H2O2 for 1h, whereupon cell viability was measured by MTS assay, caspase-3 assay was performed. Dual luciferase reporter assay was performed to verify the relationship between miR-211 of SIRT1.RESULTS： Compared to the control group, expression of miR-211 was significantly increased（P〈0.001）, the miR NA and protein expression of SIRT1 were significantly decreased（P〈0.001） in the anterior lens capsules of patients with age-related cataracts. Relative to the control group, SIRT1 miR NA and protein levels in the miR-211 mimic group were significantly reduced, cell proliferation activity significantly decreased, and caspase-3 activity was significantly increased（P〈0.001）. In the miR-211 inhibitor group, SIRT1 miRNA and protein expression were significantly increased, cell proliferation activity significantly increased, and caspase-3 activity was significantly decreased（P〈0.001）. A dual luciferase reporter assay confirmed that SIRT1 is a direct target of miR-211.CONCLUSION： miR-211 is highly expressed in the anterior lens capsules of patients with age-related cataracts. By negatively regulating the expression of SIRT1, miR-211 promotes lens epithelial cell apoptosis and inhibits lens epithelial cell proliferation.

Kinetin Inhibits Proliferation of Hepatic Stellate Cells by Interrupting Cell Cycle and Induces Apoptosis by Down-regulating Ratio of Bcl-2/Bax

Liver fibrosis is an important health problem that can further progress into cirrhosis or liver cancer,and result in significant morbidity and mortality. Inhibiting proliferation and inducing apoptosis of hepatic stellate cells（HSCs） may be the key point to reverse liver fibrosis. At present,anti-fibrosis drugs are rare. Kinetin is a type of plant-derived cytokinin which has been reported to control differentiation and induce apoptosis of human cells. In this study,the HSCs were incubated with different concentrations of kinetin. The proliferation of rat HSCs was measured by MTT assay,cell cycle and apoptosis were analyzed by flow cytometry,and the apoptosis was examined by TUNEL method. The expression of Bcl-2 and Bax proteins was detected by immunocytochemistry staining. It was found that kinetin could markedly inhibit proliferation of HSCs. In a concentration range of 2 to 8 μg/m L,the inhibitory effects of kinetin on proliferation of HSCs were increased with the increased concentration and the extension of time（P〈0.01）. Flow cytometry indicated that kinetin could inhibit the DNA synthesis from G0/G1 to S phase in a dose-dependent manner（P〈0.01）. The apoptosis rates of the HSCs treated with 8,4 and 2 μg/m L kinetin（25.62%±2.21%,15.31%±1.9% and 6.18%±1.23%,respectively） were increased significantly compared with the control group（3.81%±0.93%）（P〈0.01）. All the DNA frequency histogram in kinetin-treated groups showed obvious hypodiploid peak（sub-G1 peak）,and with the increase of kinetin concentrations,the apoptosis rate of HSCs also showed a trend of increase. It was also found that kinetin could down-regulate the expression of Bcl-2,and up-regulate the expression of Bax,leading to the decreased ratio of Bcl-2/Bax significantly. The kinetin-induced apoptosis of HSCs was positively correlated with the expression of Bax,and negatively with the expression of Bcl-2. It was concluded that kinetin can inhibit activation and proliferation of HSCs by interrupting the cell cycle at G1/S restriction point and inducing apoptosis of HSCs via reducing the ratio of Bcl-2/Bax.

Commentary on “Mandible exosomal ssc-mir-133b regulates tooth development in miniature swine via endogenous apoptosis”

This report,"Mandible exosomal ssc-mir-133b regulates tooth development in miniature swine via endogenous apoptosis" by Li et al. is an important step forward in describing the factors that control tooth development in a large animal model. That many of the regulatory miRNA pathways have been elucidated in murine species have always begged the question as to how relevant they

Dynamic Imaging of Autophagy-lysosomal Pathway and Autophagy Function Following Pulmonary Hypoxia/Reoxygenation In Vitro

Alterations of the autophagy-lysosomal pathway（ALP） and autophagy have been involved in lung ischemia-reperfusion（I/R） injury. However, dynamic imaging of ALP function under lung I/R injury particularly is not fully understood. Here we depicted the live-cell fluorescence imaging of autophagosome to monitor ALP activation and autophagy function. The p As Red2-N1-LC3 vectors were transfected into CRL-2192 NR8383（an alveolar macrophage cell line） and CCL149（an alveolar epithelial cell line） successfully. 0-h, 2-h, 4-h, and 6-h hypoxia/0-h, 2-h, 4-h, and 6-h reoxygenation were then induced with an ALP inhibitor（3-MA） or activator（rapamycin） in the culture of transfected cells separately. ALP activation was conformed by up-regulating AMPK and beclin1 expression. Apoptosis was not obvious in 2-h hypoxia/2-h reoxygenation. p As Red2-N1-LC3 CCL149 and p As Red2-N1-LC3 NR8383 cells revealed gradually enhanced As Red2 from 2-h to 6-h hypoxia/reoxygenation. As Red2 varied sensitively to 3-MA and rapamycin interventions during 2-h hypoxia/reoxygenation. Our data provides a simple method of autophagosome imaging to monitor ALP activation and autophagy function in lung I/R injury.