Fan G.-R.,Huazhong University of Science and Technology |
Yin Z.-D.,Luzhou Medical College |
Sun Y.,Huazhong University of Science and Technology |
Chen S.,Huazhong University of Science and Technology |
And 5 more authors.
Brain Research | Year: 2013
The time course of aminoglycoside neurotoxic effect on cochlear nucleus is still obscure. We examined dynamic pathological changes of dorsal cochlear nucleus (DCN) and investigated whether apoptosis or autophagy was upregulated in the neurotoxic course of kanamycin on DCN after kanamycin treatment. Rats were treated with kanamycin sulfate/kg/day at a dose of 500 mg by subcutaneous injection for 10 days. Dynamic pathological changes, neuron density and neuron apoptosis of the DCN were examined at 1, 7, 14, 28, 56, 70 and 140 days after kanamycin treatment. The expressions of JNK1, DAPK2, Bcl-2, p-Bcl-2, Caspase-3, LC3B and Beclin-1 were also detected. Under transmission electron microscopy, the mitochondrial swelling and focal vacuoles as well as endoplasmic reticulum dilation were progressively aggravated from 1 day to 14 days, and gradually recovered from 28 days to 140 days. Meanwhile, both autophagosomes and autolysosomes were increased from 1 day to 56 days. Only few neurons were positive to the TUNEL staining. Moreover, neither the expressions of caspase-3 and DAPK2 nor neurons density of DCN changed significantly. LC3-II was drastically increased at 7 days. Beclin-1 was upgraded at 1 and 7 days. P-Bcl-2 increased at 1, 7, 14 and 28 days. JNK1 increased at 7 days, and Bcl-2 was downgraded at 140 days. LC3-B positive neurons were increased at 1, 7 and 14 days. These data demonstrated that the neurons damage of the DCN caused by kanamycin was reversible and autophagy was upregulated in the neurotoxic course of kanamycin on DCN through JNK1-mediated phosphorylation of Bcl-2 pathway. © 2013 Elsevier B.V. All rights reserved.
Wu L.,Huazhong University of Science and Technology |
Wu L.,Central South University |
Sun Y.,Huazhong University of Science and Technology |
Hu Y.-J.,Huazhong University of Science and Technology |
And 8 more authors.
PLoS ONE | Year: 2012
Aging has been associated with mitochondrial DNA damage. P66Shc is an age-related adaptor protein that has a substantial impact on mitochondrial metabolism through regulation of the cellular response to oxidative stress. Our study aimed to establish a D-galactose (D-gal)-induced inner ear aging mouse model and to investigate the potential role of p66Shc and its serine 36-phosphorylated form in the inner ear during aging by using this model. Real-time PCR was performed to detect the mtDNA 3873-bp deletion and the level of p66Shc mRNA in the cochlear lateral wall. Western blot analysis was performed to analyze the total and mitochondrial protein levels of p66Shc and the level of Ser36-P-p66Shc in the cochlear lateral wall. Immunofluoresence was performed to detect the location of the Ser36-P-p66Shc expression in the cochlear lateral wall. The results showed that the accumulation of the mtDNA 3873-bp deletion, total and mitochondrial protein levels of p66Shc and level of Ser36-P-p66Shc were significantly increased in the cochlear lateral wall of the D-gal-treated group when compared to the control group and that Ser36-P-p66Shc was mainly localized in the cytoplasm of the cells in the stria vascularis. During aging, the oxidative stress-related increase of p66Shc and Ser36-P-p66Shc might be associated with the accumulation of the mtDNA 3873-bp deletion in the inner ear. © 2012 Wu et al.
Chen J.,Huazhong University of Science and Technology |
Zhang S.,Huazhong University of Science and Technology |
Li Y.,Huazhong University of Science and Technology |
Tang Z.,Huazhong University of Science and Technology |
And 2 more authors.
Tumor Biology | Year: 2014
Proliferating cancer cells preferentially use anaerobic glycolysis rather than oxidative phosphorylation for energy production. Hexokinase 2 (HK2) is highly expressed in many malignant cells and is necessary for anaerobic glycolysis. The role of HK2 in laryngeal squamous cell carcinoma (LSCC) is unknown. In this study, the expression of HK2 in LSCC was investigated and the effect of inhibiting HK2 expression with small hairpin RNA (shRNA) on tumor growth was investigated. Using immunohistochemistry, HK2 expression was assessed in LSCC tissues. Human laryngeal carcinoma Hep-2 cells were stably transfected with a plasmid expressing HK2 shRNA (pGenesil-1.1-HK2) and were compared to control cells with respect to the cell cycle, cell viability, apoptosis, and their ability to form xenograft tumors. HK2 expression was significantly higher in LSCC than in papilloma or glottis polypus. Tumor samples of higher T, N, and TNM stage often had stronger HK2 staining. HK2 shRNA reduced HK2 mRNA, protein levels, and HK activity in Hep-2 cells. HK2 cells expressing shRNA demonstrated a higher G0-G1 ratio, increased apoptosis, and reduced viability. Xenograft tumors derived from cells expressing HK2 shRNA were smaller and had lower proliferation than those from untransfected or control-plasmid-transfected cells. In conclusion, depletion of HK2 expression resulted in reduced xenograft tumor development likely by reducing proliferation, altering the cell cycle, reducing cell viability and activating apoptosis. These data suggest that HK2 plays an important role in the development of LSCC and represents a potential therapeutic target for LSCC. © 2013 International Society of Oncology and BioMarkers (ISOBM).
Chen X.,Huazhong University of Science and Technology |
Zhao X.,Huazhong University of Science and Technology |
Hu Y.,Huazhong University of Science and Technology |
Lan F.,Huazhong University of Science and Technology |
And 6 more authors.
Gene Therapy | Year: 2015
There is no definitive conclusion concerning the spread of viral vectors to the brain after a cochlear inoculation. In addition, some studies have reported different distribution profiles of viral vectors in the central auditory system after a cochlear inoculation. Thus, rats were grouped into either a mimetic aging group or a young group and transfected with adenoviral vectors (AdVs) by round window membrane injection. The distribution of AdV in central nervous system (CNS) was demonstrated in the two groups with transmission electron microscopy and immunofluorescence. We found that the AdV could disseminate into the CNS and that the neuronal damage and stress-induced GRP78 expression were reduced after transfection with PGC-1α, as compared with the control vectors, especially in the mimetic aging group. We also found that the host immune response was degraded in CNS in the mimetic aging group after transduction through the cochlea, as compared with the young group. These results demonstrate that viral vectors can disseminate into the CNS through the cochlea. Moreover, mimetic aging induced by D-galactose could facilitate the spread of viral vectors into the CNS from the cochlea. These findings may indicate a new potential approach for gene therapy against age-related diseases in the CNS. © 2015 Macmillan Publishers Limited. All rights reserved.
Wang X.-L.,Key Laboratory of Neurological Disease |
Wang X.-L.,Hubei University of Chinese Medicine |
Wang X.-L.,Huazhong University of Science and Technology |
Zeng J.,Huazhong University of Science and Technology |
And 15 more authors.
Journal of Alzheimer's Disease | Year: 2014
Abnormal hyperphosphorylation of microtubule-associated protein tau is involved in the pathogenesis of several neurodegenerative disorders including Alzheimer's disease (AD). Helicobacter pylori (H. pylori) infection has been reported to be related with a high risk of AD, but the direct laboratory evidence is lacking. Here we explored the effect of H. pylori infection on tau phosphorylation. The results showed that H. pylori filtrate induced significant tau hyperphosphorylation at several AD-related tau phosphorylation sites, such as Thr205, Thr231, and Ser404, both in mouse neuroblastoma N2a cells and rat brains with activation of glycogen synthase kinase-3β (GSK-3β). Application of GSK-3 inhibitors efficiently attenuated the H. pylori-induced tau hyperphosphorylation. Our data provide evidence supporting the role of H. pylori infection in AD-like tau pathology, suggesting that H. pylori eradication may be beneficial in the prevention of tauopathy. © 2015 IOS Press and the authors. All rights reserved.