Mitophagy, a selective autophagy of mitochondria, clears up damaged mitochondria to maintain cell homeostasis. We performed high-content analysis (HCA) to detect the increase of PINK1, an essential protein controlling mitophagy, in hepatic cells treated with several nanoparticles (NPs). PINK1 immunofluorescence-based HCA was more sensitive than assays and detections for cell viability and mitochondrial functions. Of which, superparamagnetic iron oxide (SPIO)-NPs or graphene oxide-quantum dots (GO-QDs) was selected as representatives for positive or negative inducer of mitophagy. SPIO-NPs, but not GO-QDs, activated PINK1-dependent mitophagy as demonstrated by recruitment of PARKIN to mitochondria and degradation of injured mitochondria. SPIO-NPs caused the loss of mitochondrial membrane potential, decrease in ATP, and increase in mitochondrial reactive oxide species and Ca2+. Blocking mitophagy with PARKIN siRNA aggravated the cytotoxicity of SPIO-NPs. Taken together, PINK1 immunofluorescence-based HCA is considered to be an early, sensitive, and reliable approach to evaluate the bioimpacts of NPs. 相似文献
Few studies have examined coercive sex and HIV vulnerabilities among men who have sex with men (MSM) in China. The present study seeks to compare individual characteristics between MSM who did and did not experience coercive sex at their MSM sexual debut and to identify HIV risk factors correlated with coercive sex at MSM sexual debut. In 2007, we recruited 167 MSM in Beijing, China by peer-referred social network sampling. Each participant then completed self-administered questionnaires regarding their sexual experiences and practices. Results show that 14% of participants reported coercive sex at MSM sexual debut, of whom 48% reported recent unprotected anal intercourse (UAI). Coercive sex at MSM sexual debut was significantly associated with UAI [adjusted odds ratio (AOR): 5.38, 95% confidence interval: 1.95–14.87] and lifetime number of male sex partners (AOR: 7.25, 95% CI: 2.39–22.01). Coercive sex is harming MSM in China and should be immediately addressed by researchers, public health officials, and MSM community stakeholders. 相似文献
We investigated the effect of increased intracellular reactive oxygen species(ROS) on SOCS-3 expression in 3T3-L1 adipocytes. Increased intracellular ROS levels in 3T3-L1 adipocytes were achieved by two methods of exposure to H2O2 and the occurrence of oxidative stress in cells was assessed by flow cytometry . Expression of SOCS-3 mRNA and that of some adipokines were measured by real time PCR. The level of SOCS-3 protein was determined by western blot. The effect of the antioxidant alpha-lipoic acid was also investigated. Both the relatively mild increased intracellular ROS and the acute but transient increased ROS elevated the levels of SOCS-3 mRNA and protein in 3T3-L1 adipocytes, acompanied with elevated levels of TNF-α mRNA and resistin mRNA and the decreased levels of adiponectin mRNA and secretory adiponectin in culture medium. α-lipoic acid could attenuate the effects of ROS on 3T3-L1 adipocytes. We hypothesized that in mature 3T3-L1 adipocytes, SOCS-3 could be upregulated directly by the induction of increased intracellular ROS and to some extent which was up-regulated by adipokine modulation.
Inhibitors of nuclear factor (NF)-κB pathway have shown potential anti-tumor activities. However, it is not fully elucidated in gastric cancer.
Methods
Firstly, we screened the inhibitory effect of pharmacologic NF-κB inhibitors on cell viability of human gastric cancer cells via CCK-8 assay. Next, cell apoptosis, cell cycle distribution, and mitochondrial membrane potential after BAY 11-7082 treatment were detected by annexin V staining, propidium iodide staining, TUNEL, and JC-1 assays in human gastric cancer HGC-27 cells. Expression of regulatory factors for apoptosis and cell cycle were measured by western blot. Finally, human gastric cancer xenograft model was established to verify the anti-tumor effects of BAY 11-7082 in vivo. Cellular apoptosis and growth inhibition in subcutaneous tumor section were detected by TUNEL and immunohistochemistry assays.
Results
BAY 11-7082 exhibited rapid and potent anti-tumor effects on gastric cancer cells in vitro within a panel of NF-κB inhibitors. BAY 11-7082 induced rapid apoptosis in HGC-27 cells through activating the mitochondrial pathway, as well as down-regulation of Bcl-2 and up-regulation of Bax. BAY 11-7082 also induced S phase arrest through suppressing Cyclin A and CDK-2 expression. Xenograft model confirmed the anti-tumor effects of BAY 11-7082 on apoptosis induction and growth inhibition in vivo.
Conclusions
Our results demonstrated that BAY 11-7082 presented the most rapid and potent anti-tumor effects within a panel of NF-κB inhibitors, and could induce cellular apoptosis and block cell cycle progression both in vitro and in vivo, thus providing basis for clinical application of BAY 11-7082 in gastric cancer cases. 相似文献
Clinical Rheumatology - There were overlaps between the article recently published in this journal [1] and the previous publications from the authors’ group [2-4] that they did not cite.] 相似文献