Transferrin (Tf), an iron-transporting serum glycoprotein that binds to receptors overexpressed at the surface of glioma cells, was chosen as the ligand to develop Tf-conjugated PEGylated nanoscaled graphene oxide (GO) for loading and glioma targeting delivery of anticancer drug doxorubicin (Dox) (Tf-PEG-GO-Dox). Tf-GO with lateral dimensions of 100-400 nm exhibited a Dox loading ratio up to 115.4%. Compared with Dox-loaded PEGylated GO (PEG-GO-Dox) and free Dox, Tf-PEG-GO-Dox displayed greater intracellular delivery efficiency and stronger cytotoxicity against C6 glioma cells. A competition test showed that Tf was essential to glioma targeting in vitro. The HPLC assay for Dox concentration in tumor tissue and contrapart tissue of the brain demonstrated that Tf-PEG-GO-Dox could deliver more Dox into tumor in vivo. The life span of tumor bearing rats after the administration of Tf-PEG-GO-Dox was extended significantly compared to the rats treated with saline, Dox, and PEG-GO-Dox. In conclusion, we developed Tf-PEG-GO-Dox which exhibited significantly improved therapeutic efficacy for glioma both in vitro and in vivo.

There is growing evidence that oxidative stress plays critical roles in the pathogenesis of cardiac remodeling. In the present study, we established a rat model of passive smoking and investigated the antioxidant effects of hydrogen sulfide (H2S) on smoking-induced left ventricular remodeling. Cardiac structure and function were evaluated using 2-dimensional echocardiography. Myocardial fibrosis was detected by Masson's trichrome staining and immunohistochemistry. Oxidative stress was assessed by measuring malondialdehyde levels, superoxide dismutase and glutathione peroxidase activities, and reactive oxygen species generation in the myocardium. Neonatal rat cardiomyocytes transfected with specific siRNA and exposed to cigarette smoke condensate and H2S donor sodium hydrosulfide were used to confirm the involvement of Nrf2 and PI3K/Akt signaling in the antioxidant effects of H2S. Our results indicated that H2S could protect against left ventricular remodeling in smoking rats via attenuation of oxidative stress. Moreover, H2S was also found to increase the phosphorylation of Akt and GSK3β and decrease the nuclear expression of Fyn, which consequently leads to nuclear translocation of Nrf2 and elevated expression of HO-1 and NQO1. In conclusion, H2S may exert antioxidant effects on left ventricular remodeling in smoking rats via PI3K/Akt-dependent activation of Nrf2 signaling.

Mild hypothermia is an effective therapeutic strategy to improve poor neurological outcomes in patients following cardiac arrest (CA). However, the underlying mechanism remains unclear. The aim of the study was to evaluate the effect of mild hypothermia on intracellular autophagy and mitophagy in hippocampal neurons in a rat model of CA. CA was induced in Sprague-Dawley (SD) rats by asphyxia for 5 min. After successful resuscitation, the surviving rats were randomly divided into two groups, the normothermia (NT) group and the hypothermia (HT) group. Mild hypothermia (32 °C) was induced following CA for 4 h, and animals were rewarmed at a rate of 0.5 °C/h. Neurologic deficit scores (NDS) were used to determine the status of neurological function. Cytoplasmic and mitochondrial protein from the hippocampus was extracted, and the expression of LC3B-II/I and Parkin were measured as markers of intracellular autophagy and mitophagy, respectively. Of the 60 rats that underwent CA, 44 were successfully resuscitated (73 %), and 33 survived until the end of the experiment (55 %). Mild hypothermia maintained eumorphism of nuclear and mitochondrial structures and significantly improved NDS (p < 0.05). Expression of LC3B-II/I and Parkin in hippocampal nerve cells were significantly increased (p < 0.05) in the NT group relative to the control. Meanwhile, mild hypothermia reduced the level of LC3B-II/I and Parkin (p < 0.05) relative to the NT group. Mild hypothermia protected mitochondria and improved neurological function following CA and resuscitation after ischemia/reperfusion (I/R) injury, likely by reducing excessive autophagy and mitophagy in neurons.

Doxorubicin (Dox) is widely used for the treatment of solid tumors but its clinical utility on glioma is limited. In this study, we developed a novel nano-scale drug delivery system employing biodegradable nanoparticle (NP) as carriers to load Dox. Transferrin (Tf) was conjugated to the surface of NP to specifically target the NP to glioma. Tf-NP-Dox was prepared via emulsification-solvent evaporation method, and characterized for the size, Drug loading capacity (DLC), entrapment efficiency, and Tf number on the surface. The antitumor efficiency in vitro was evaluated via CCK-8 assay. The transmembrane transportation was evaluated via HPLC assay. The antitumor efficiency in vivo was assessed in C6 glioma intracranial implant rat model. The average diameter of Tf-NP-Dox was 100 nm with ∼32 Tf molecules on the surface. DLC was 4.4%. CCK-8 assay demonstrated much stronger cytotoxicity of Tf-NP-Dox to C6 glioma cells compared to NP-Dox or Dox. HPLC assay showed that Tf-NP-Dox transported Dox into C6 cells with high efficiency. In vivo, Tf-NP-Dox could transport Dox into tumors compare to contralateral part, with tumor inhibitory ratio and survival higher than NP-Dox or Dox. Taken together, our results suggest that Tf-NP-Dox exhibits better therapeutic effects against glioma both in vitro and in vivo, and is a potential nano-scale drug delivery system for glioma chemotherapy.

BACKGROUND: Cardiac arrest (CA) is a common and serious event in emergency medicine. Despite recent improvements in resuscitation techniques, the survival rate of patients with CA is unchanged. The present study was undertaken to observe the effect of mild hypothermia (MH) on the reactive oxygen species (ROS) and the effect of neurological function and related mechanisms. METHODS:Sixty-five healthy male Sprague Dawley (SD) adult rats were randomly (random number) divided into 2 groups: blank control group (n=5) and CPR group (n=60). CA was induced by asphyxia. The surviving rats were randomly (random number) divided into two groups: normothermia CPR group (NT) and hypothermia CPR group (HT). Normothermia of 37 °C was maintained in the NT group after return of spontaneous circulation (ROSC), hypothermal intervention of 32 °C was carried out in the HT group for 4 hours immediately after ROSC. Both the NT and HT groups were then randomly divided into 2 subgroups 12 hours and 24 hours after ROSC (NT-12, NT-24, HT-12, HT-24 subgroups). During observation, the neurological defi cit scores (NDSs) was recorded, then the bilateral hippocampi were obtained from rats' head, and monoplast suspension of fresh hippocampus tissue was made immediately to determine the level of intracellular ROS by flow cytometry. Transmission electron microscope was used to observe the ultramicro changes of cellular nucleus and mitochondria. Reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the expression of caspase-3 mRNA, and western-blotting (WB) was used to determine the level of LC3 in frozen hippocampus tissue. Measured data were analyzed with paired sample t test and One-Way ANOVA.RESULTS: Of 60 rats with CA, 44 (73%) were successfully resuscitated and 33 (55%) survived until the end of the experiment. The NDSs of rats in the NT and HT groups were more signifi cantly reduced than those in the BC group (F=8.107, P<0.05), whereas the NDSs of rats in the HT-12 and HT-24 subgroups were significantly increased in comparison with those NDSs of rats in the NT-12 and NT-24 subgroups, respectively (t=9.692, P<0.001; t=14.374, P<0.001). The ROS in hippocampus nerve cells in the NT and HT groups signifi cantly increased compared to the BC group (F=16.824, P<0.05), whereas the ROS in the HT-12 and HT-24 subgroups significantly reduced compared with that ROS in the respectively (t=9.836, P<0.001; t=7.499, P<0.001). The expression of caspase-3 mRNA in hippocampus nerve cells in the NT and HT groups were signifi cantly increased compared to the BC group (F=24.527, P<0.05), whereas the expression of caspase-3 mRNA in rats of the HT-12 and HT-24 subgroups was signifi cantly reduced compared to the respectively (t=6.935, P<0.001; t=4.317, P<0.001). The expression of LC3B-II/I in hippocampus nerve cells of rats in the NT and HT groups signifi cantly www.wjem.org 299 World J Emerg Med, Vol 5, No 4, 2014 increased compared to the BC group (F=6.584, P<0.05), whereas the expression of LC3B-II/I in rats of the HT-12 and HT-24 ...