Effects of leptin on proliferation and differentiation of hypoxic rat retinal progenitor cells in vitro / 南方医科大学学报

OBJECTIVE@#To investigate the the effects of leptin on the proliferation, differentiation and PTEN expression of rat retinal progenitor cells (RPCs) cultured under hypoxic condition.@*METHODS@#SD rat RPCs were cultured in normoxic conditions or exposed to hypoxia in the presence of 0, 0.3, 1.0, 3.0, 10, and 30 nmol/L leptin for 12, 48 and 72 h, and the cell viability was assessed using cell counting kit 8 (CCK 8) assay. The RPCs in primary culture were divided into control group, hypoxia group, and hypoxia+leptin group, and after 48 h of culture, the cell medium was replaced with differentiation medium and the cells were further cultured for 6 days. Immunofluorescence staining was employed to detect the cells positive for β-tubulin III and GFAP, and Western blotting was used to examine the expression of PTEN at 48 h of cell culture.@*RESULTS@#The first generation of RPCs showed suspended growth in the medium with abundant and bright cellular plasma and formed mulberry like cell spheres after 2 days of culture. Treatment with low-dose leptin (below 3.0 nmol/L) for 48 h obviously improved the viability of RPCs cultured in hypoxia, while at high concentrations (above 10 nmol/L), leptin significantly suppressed the cell viability (P < 0.05). The cells treated with 3.0 nmol/L leptin for 48 h showed the highest viability (P < 0.05). After treatment with 3.0 nmol/L leptin for 48 h, the cells with hypoxic exposure showed similar GFAP and β-tubulin Ⅲ positivity with the control cells (P>0.05), but exhibited an obvious down-regulation of PTEN protein expression compared with the control cells (P < 0.05).@*CONCLUSION@#In rat RPCs with hypoxic exposure, treatment with low dose leptin can promote the cell proliferation and suppress cellular PTEN protein expression without causing significant effects on cell differentiation.

Inhibitory effect of isolinderalactone on growth of human breast cancer MCF-7 cells and its mechanism / 中草药

Objective: To study the effects and the mechanism of isolinderalactone on inhibiting the growth of human breast cancer MCF-7 cells. Methods: Human breast cancer MCF-7 cells were cultured in vitro and treated respectively with indicated concentrations of isolinderalactone by cell culture technique. The proliferation rate was detected by MTT method; Flow cytometry and TUNEL assay were used to observe the effects of isolinderalactone on cell cycle, mitochondrial membrane potential and apoptosis in MCF-7 cells; The apoptosis related protein expression levels were determined by Western blotting. Results: Isolinderalactone significantly inhibited the proliferation of MCF-7 cells by inducing cell apoptosis in a time and concentration dependent manner and induced cell cycle arrest at G2/M phases. The mitochondrial membrane potential was depolarized; And isolinderalactone up-regulated the expressions of apoptosis related proteins Bax and cleaved Caspase-3 and down-regulated the expressions of apoptosis related proteins Bcl-2. Conclusion: Isolinderalactone shows obvious anti-cancer activities by inducing cell apoptosis. The mechanism of inducing apoptosis may be associated with the reduction of mitochondrial membrane potential and activation of caspase pathway.

Observation on the efficacy of Conbercept for chronic central serous chorioretinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe the efficacy of intravitreal conbercept injection for chronic central serous chorioretinopathy (CSC).METHODS: Nine eyes of 9 patients diagnosed as chronic CSC between October 2015 to May 2016 were treated with an intravitreal injection of conbercept (0.5mg/0.05mL) (six patients were given the same does of intravitreal injection again at 1mo after the first injection).Follow-up observation was at 1, 2, and 6mo after injection.Observed indicators included best-corrected visual acuity (BCVA), intraocular pressure, optical coherence tomography (OCT), fundus fluorescein angiography (FFA), choroidal indocyanine green angiography (ICGA), macular fovea thickness (CMT), subfoveal choroidal thickness (SFCT).RESULTS:Seven of the 9 patients responded significantly to the drug, while 2 patients had no response.The CMT was 373.12±72.43μm at baseline, which decreased significantly to 332.05±67.13μm, 282.24±62.30μm and 225.56±71.08μm at 1, 2 and 6mo after the intravitreal injection.The mean thickness of SFCT was 422.11±64.82μm before treatment.The choroidal thickness of non-responsive patients before treatment was below average, respectively 353μm and 365μm.The SFCT of 1, 2, and 6mo after treatment was 391.45±75.24μm, 365.53±63.07μm, 355.40±66.65μm.Before treatment and 1mo after, there was no significant difference (P=0.074), but there was statistically significant (P0.05).CONCLUSION: Intravitreal conbercept injection in chronic CSC may have some effect in accelerating subertinal fluid resolution and decreasing the CMT.The SFCT within 6mo after treatment was significantly lower than pretreatment.The SFCT may be an indicator of whether patients respond.