摘要:目的: 探討在血管緊張素Ⅱ(AngⅡ)誘導血管平滑肌細胞(VSMCs)NOX1基因表達增加中線粒體所起的作用。 方法 :體外培養大鼠主動脈VSMCs,用線粒體呼吸鏈的抑制劑阻斷線粒體的作用,用熒光實時定量PCR檢測NOX1基因表達的量。 結果 :AngⅡ能夠誘導 NOX1基因的表達增加,線粒體呼吸鏈的抑制劑能夠抑制上述這一作用。 結論 :在大鼠的VSMCs中,AngⅡ誘導NOX1的增加通過線粒體呼吸的作用。Abstract: Objective: To detect the role of mitochondria involved in Angiotensin Ⅱ(Ang Ⅱ) induced NOX1 gene expression. Methods :Rat aortic vascellum smooth muscle cells(VSMCs) were cultured in vitro,and were treated with or without some inhibitors of complexs in mitochondrial respiratory chain. Realtime RTPCR was used to calculate the expression of NOX1 mRNA. Results :AngⅡ stimulated NOX1 gene expression,while some inhibitors of complexs in mitochondrial respiratory chain attenuated this progress.〖WTHZ〗Conclusion : Mitochondrial respiratory chain mediates expression of NOX1 gene in VSMCs by AngⅡ.
ObjectiveTo explore the effects and molecular mechanisms of histone methylase G9a inhibitor BIX-01294 on apoptosis in esophageal squamous cell carcinoma (ESCC).MethodsMTT assay and Colony-forming Units were adopted to determine the effects of BIX-01294 on the growth and proliferation of ESCC cell lines EC109 and KYSE150. Flow cytometry was used to analyze the apoptosis status of ESCC cells after the treatment of BIX-01294. The effects of BIX-01294 treatment on the expressions of G9a catalytic product H3K9me2, DNA double-strand break (DSB) markers, and apoptosis-related proteins were detected by Western blotting.ResultsBIX-01294 inhibited the growth of EC109 and KYSE150 cells in a dose-dependent manner (P<0.05), and BIX-01294 with the inhibitory concentration 50% (IC50) significantly inhibited the formation of colony (P<0.05). After 24 hours treatment of BIX-01294 (IC50), the apoptosis rate of EC109 cells increased from 11.5%±2.1% to 42.5%±5.4%, and KYSE150 cells from 7.5%±0.9% to 49.2%±5.2% (P<0.05). The expression level of the G9a catalytic product, H3K9me2, significantly decreased (P<0.05); while the expression of the DSB marker γH2AX was dramatically enhanced (P<0.05). We also found that the mitochondrial apoptosis pathway was activated and the expression levels of cleaved caspase3 and cleaved PARP were significantly elevated (P<0.05).ConclusionBIX-01294, the inhibitor of methyltransferase G9a, prompted apoptosis in ESCC cells by inducing DSB damage and activating mitochondrial apoptosis pathway.
The present study was to investigate the effects of infusing remifentanil-poly-caprolactone (REM-PCL) through the abdominal aorta on spinal cord ischemia reperfusion injury (SCIRI). The model of SCIRI was created by clamping the infrarenal aortic in thirty-six New Zealand white rabbits, which were randomly divided into sham group (group S), control group (group C), and REM-PCL group (group R) with 12 rabbits in each one. The spinal cord microcirculatory blood flow (SCMBF) and blood flow rate (BFR) were monitored before ischemia, 15 min, 30 min, 60 min and 120 min after reperfusion, respectively. Neurologic Function was evaluated before ischemia, 6h, 12h and 24h after reperfusion. The concentration of serum neuron-specific enolase (NSE), interleukin-lβ (IL-lβ) and interleukin-8 (IL-8) were monitored before ischemia, 45 min after ischemia, 30 min, 60 min, 6 h, 12 h and 24 h after reperfusion. The abnormal rate of motor neuron of spinal cord tissues and the level of superoxide dismutase (SOD), reactive oxygen species (ROS), glutathione peroxidase (GSH-PX), malondialdehyde (MDA), total anti-oxidation capacity (T-AOC) and mitochondrial swelling degree (MSD) in neural mitochondria were determined before ischemia, 45 min after clamping, 60 min and 120 min after reperfusion. As a result, the neural mitochondrial SOD, GSH-PX and T-AOC decreased while ROS, MDA, MSD, IL-lβ, IL-8 and NSE distinctly increased after clamping of the abdominal aorta as compared to the value before ischemia in group C (P < 0.01). Neurologic function scores recovered more rapidly in group R than those in group C during reperfusion (P < 0.01). The neural mitochondrial SOD, GSH-PX and T-AOC were distinctly higher while ROS, MDA, MSD, IL-lβ, IL-8 and NSE were distinctly lower in group R than those in group C (P < 0.01). The abnormal rate of motor neuron was significantly higher in group C during reperfusion than that in group R (P < 0.01). It has been shown that the intra-aortic REM-PCL infusion can alleviate SCIRI by inhibiting inflammatory response and improving mitochondrial anti-oxidation capacity.
Leber’s hereditary optic neuropathy (LHON) is a paradigm maternal hereditary eye disease, mainly involving the retinal and macular fibers of the optic disc in the anterior ethmoid plate of the sclera. LHON has the characteristics of sex bias among males and incomplete penetrance. Primary mitochondrial DNA mutations m.11778G>A, m. 14484T>C, m.3460G>A are the molecular basis of LHON. However, other risk factors, such as secondary mitochondrial DNA mutations, mitochondrial haplotypes, nuclear modification genes, estrogen, vitamin B12 and environmental factors, work together to affect its phenotypic expression. The clinical diagnosis of LHON mainly limited to the detection of the primary mutation site of mitochondrial DNA. Therefore, comprehensive analysis of multiple risk factors of LHON will facilitate to construct multi-dimensional model of prevention, diagnosis and treatment system, which provide accurate and individualized medical services for patients. These may alleviate the incidence in LHON families. It also provides new ideas and different angles for the in-depth study of the pathogenesis of LHON.
The endoplasmic reticulum (ER) is physically connected to mitochondria through the specific sub-domain,called mitochondria-associated endoplasmic reticulum membranes (MAMs). These contacts are involved in calcium signaling,lipid transferring,mitochondrial fission and fusion and energy metabolism. Recently,MAMs alterations have been identified to associate with some diseases,including neurodegenerative diseases,obesity,cardiovascular diseases and cancer. Therefore,in this paper,we introduce the structure,function and detection methods of MAMs. Besides,we also summarize the potential role of MAMs in these diseases. In any case,the signaling at the MAMs might be a promising pharmacological target for several diseases.
Objective To review the research progress of mitochondrial dynamics mediated by optic atrophy 1 (OPA1) in skeletal system diseases. MethodsThe literatures about OPA1-mediated mitochondrial dynamics in recent years were reviewed, and the bioactive ingredients and drugs for the treatment of skeletal system diseases were summarized, which provided a new idea for the treatment of osteoarthritis. Results OPA1 is a key factor involved in mitochondrial dynamics and energetics and in maintaining the stability of the mitochondrial genome. Accumulating evidence indicates that OPA1-mediated mitochondrial dynamics plays an important role in the regulation of skeletal system diseases such as osteoarthritis, osteoporosis, and osteosarcoma. Conclusion OPA1-mediated mitochondrial dynamics provides an important theoretical basis for the prevention and treatment of skeletal system diseases.
Objective To investigate the changes in mitochondrial morphology, structure and function in rats with severe intermittent hypoxia, as well as the effects of intermittent hypoxia and its severity on cognitive function. Methods A total of 18 rats were selected to construct a model of severe intermittent hypoxia, which were divided into a normal control group, an intermittent air control group, and a 5% intermittent hypoxia group for 8 weeks, with 6 rats in each group. The structural and functional changes of mitochondria in the hippocampal CA1 region were observed. A total of 30 rats were randomly divided into 5 groups: a normal control group, an intermittent air control group, a 5% intermittent hypoxia 4-week group, a 5% intermittent hypoxia 6-week group, and a 5% intermittent hypoxia 8-week group, with 6 rats in each group. The cognitive function of the rats in each group was evaluated by Morris water maze experiment. Results In the mitochondria of the hippocampal CA1 region of severely intermittent hypoxic rats, bilayer membranes or multilayer membranes were visible, the mitochondria were swollen, cristae were broken and vacuolated, and their respiratory function was significantly weakened, the membrane permeability was increased, and the membrane potential was reduced. In the Morris water maze, there was no significant difference in swimming speed between the rats. With the prolongation of intermittent hypoxia action time, the latency of finding the hidden platform in each group of rats increased significantly, and the residence time of the target quadrant decreased significantly. Conclusions Mitochondrial structure in the hippocampal CA1 region of the rat brain is destroyed during severe intermittent hypoxia, and dysfunction and cognitive impairment occur. With the prolongation of intermittent hypoxic injury, the degree of cognitive impairment worsens.
ObjectiveTo elucidate the metabolic characteristics of mitochondria in sepsis and review its cellular mechanism, so as to provide new ideas for the treatment of sepsis. MethodThe previous literatures and latest research results about mitochondrial metabolism during sepsis were reviewed. ResultsAt present, the researchers were not only concerned about the inflammatory response of sepsis, but also concerned about the systemic metabolic disorder caused by sepsis. It was believed that the damage of mitochondria caused by sepsis was one of the main reasons for the disorder of cell metabolism. During the sepsis, the patient’s metabolism had changed, for example, enhancement of aerobic glycolysis, lactic acid accumulation, elevated levels of fatty acids and triglycerides in blood, and so on. ConclusionMetabolic change during sepsis is related to mitochondria, which can provide some new methods for treatment of sepsis.
Objective To investigate the effect of M2-like macrophage/microglia-derived mitochondria transplantation in treatment of mouse spinal cord injury (SCI). Methods BV2 cells were classified into M1 (LPS treatment), M2 (IL-4 treatment), and M0 (no treatment) groups. After receiving M1 and M2 polarization, BV2 cells received microscopic observation, immunofluorescence staining [Arginase-1 (Arg-1)] and flow cytometry [inducible nitric oxide synthase (iNOS), Arg-1] to determine the result of polarization. MitoSox Red and 2, 7-dichlorodi-hydrofluorescein diacetate (DCFH-DA) stainings were used to evaluate mitochondrial function difference. Mitochondria was isolated from M2-like BV2 cells through differential velocity centrifugation for following transplantation. Then Western blot was used to measure the expression levels of the relevant complexes (complexes Ⅱ, Ⅲ, Ⅳ, and Ⅴ) in the oxidative phosphorylation (OXPHOS), and compared with M2-like BV2 cells to evaluate whether the mitochondria were obtained. Thirty-six female C57BL/6 mice were randomly divided into 3 groups (n=12). Mice from sham group were only received the T10 laminectomy. After the T10 spinal cord injury (SCI) model was prepared in the SCI group and mitochondria transplantation (MT) group, mitochondrial storage solution and mitochondria (100 μg) derived from M2-like BV2 cells were injected into the injured segment, respectively. After operation, the Basso Mouse Scale (BMS) score was performed to evaluate the motor function recovery. And immunofluorescence staining, lycopersicon esculentum agglutinin (LEA)-FITC staining, and ELISA [vascular endothelial growth factor A (VEGFA)] were also performed. Results After polarization induction, BV2 cells in M1 and M2 groups showed specific morphological changes of M1-like and M2-like macrophages, respectively. Immunofluorescence staining showed that the positive expression of M2-like macrophages marker (Arg-1) was significantly higher in M2 group than in M0 group and M1 group (P<0.05). Flow cytometry showed that the expression of M1-like macrophage marker (iNOS) was significantly higher in M1 group than in M0 group and M2 group (P<0.05), and the expression of Arg-1 was significantly higher in M2 group than in M0 group and M1 group (P<0.05). MitoSox Red and DCFH-DA stainings showed that the fluorescence intensity of the M2 group was significantly lower than that of the M1 group (P<0.05), and there was no significant difference with the M0 group (P>0.05). The M2-like BV2 cells-derived mitochondria was identified through Western blot assay. Animal experiments showed that the BMS scores of MT group at 21 and 28 days after operation were significantly higher than those of SCI group (P<0.05). At 14 days after operation, the number of iNOS-positive cells in MT group was significantly lower than that in SCI group (P<0.05), but still higher than that in sham group (P<0.05); the number of LEA-positive cells and the expression of VEGFA in MT group were significantly more than those in the other two groups (P<0.05). Conclusion M2-like macrophage/microglia-derived mitochondria transplantation can promote angiogenesis and inhibit inflammatory M1-like macrophage/microglia polarization after mouse SCI to improve function recovery.
