1.Nuclear factor кB activation co-regulated by protein kinase B and glycogen synthase kinase 3β during amyloid-β 25-35 -induced apoptosis in rat pheochromocytoma cells
Yumei LI ; Linping CHENG ; Sijun REN ; Yongping DENG ; Shengqiang CHEN
Chinese Journal of Geriatrics 2010;29(7):597-600
Objective To investigate the relationships of nuclear factor кB (NF-кB) activation with protein kinase B (Akt) and glycogen synthase kinase 3β (GSK-3β) during amyloid-β (Aβ) (25-35) -induced apoptosis in pheochromocytoma cells (PC12 cells) of rats. Methods Apoptosis in PC12 cells was induced by A(25-35). The activities of Akt, GSK-3β and NF-кB were analyzed in this process. The Akt and GSK-3β pathways were blocked by their specific inhibitors, respectively, and the relationships of Akt and, GSK-3β with NF-кB during Aβ(25-35)-induced apoptosis in PC12 cells were determined. Results Aβ(25-35) induced apoptosis was in a dose-dependent manner. With 0, 5, 10, 20 μmol/L and 40 μmol/L Aβ(25-35) treaing for 48 h, the apoptosis rates of PC12 cells were (3. 01 ± 0.03)%, (3.08 ±0.03)%, (25.32 ± 0.76)%, ( 42.88 ± 0.60 )% and ( 60.85 ± 2.39 )% , respectively. Compared to control, both Akt and GSK-3β were suppressed during apoptosis, at meantime NF-кB was activated. The inhibited Akt activity by wortmannin leaded to decreased NF-кB activatity and increased GSK-3β activatity. Suppression of GSK-3β with its specific inhibitor LiCl caused the decreased activation of NF-кB too, but it had no significant influence on Akt activity. Conclusions These results suggest that both Akt and GSK-3β are upstream regulators of NF-кB. They co-regulate the activation of NF-кB during Aβ(25-35)-induced apoptosis in PC12 cells. This study contributes to the theoretical base for the pathogenesis of Alzheimer disease (AD) , and provides a new idea to AD prevention and therapy.
2.Diagnosis and treatment of delayed gastric emptying after resection of esophageal and gastric cardia carcinoma
Sijun YAN ; Borong DENG ; Yan LIU ; Xiang CAO ; Jiejian HUANG ; Decheng QIAO
Chinese Journal of Postgraduates of Medicine 2010;33(32):5-7
Objective To investigate the causes, diagnosis and methods of prevention and treatment of delayed gastric emptying (DGE) after resection of esophageal and gastric cardia carcinoma. Methods The datas of 19 patients who had DGE after resection of esophageal and gastric cardia carcinoma in hospital from January 1993 to December 2009 were retrospectively analyzed. Results Three cases were confirmed as mechanical DGE and these patients were removed obstruction and cured by operation in time. Sixteen cases were functional DGE and were cured by conservative treatment,gastric function recovered after 7-19 d.Conclusions According to clinical manifestation,upper gastrointestinal radiography and endoscopy,the diagnosis of DGE after resection of esophageal and gastric cardia carcinoma can be confirmed. The majority of DGE are functional and the patients could be cured by conservative treatment. But the patients who have mechanical obstruction have to operate in time. The best way to prevent DGE is to improve preoperative nutrition status,enforce standard surgical manipulation,maintain effective gastrointestinal decompression and strengthen postoperative dietary control.
3.Gossypol acetic acid induces apoptosis in RAW264.7 cells via a caspase-dependent mitochondrial signaling pathway.
Sijun DENG ; Hui YUAN ; Jine YI ; Yin LU ; Qiang WEI ; Chengzhi GUO ; Jing WU ; Liyun YUAN ; Zuping HE
Journal of Veterinary Science 2013;14(3):281-289
To investigate the effects of gossypol acetic acid (GA) on proliferation and apoptosis of the macrophage cell line RAW264.7 and further understand the possible underlying mechanism responsible for GA-induced cell apoptosis, RAW264.7 cells were treated with GA (25~35 micromol/L) for 24 h and the cytotoxicity was determined by MTT assay, while apoptotic cells were identified by TUNEL assay, acridine orange/ethidium bromide staining and flow cytometry. Moreover, mitochondrial membrane potential (DeltaPsi(m)) with Rhodamine 123 and reactive oxygen species (ROS) with DCFH-DA were analyzed by fluorescence spectrofluorometry. In addition, the expression of caspase-3 and caspase-9 was assessed by Western Blot assay. Finally, the GA-induced cell apoptosis was evaluated by flow cytometry in the present of caspase inhibitors Z-VAD-FMK and Ac-LEHD-FMK, respectively. GA significantly inhibited the proliferation of RAW264.7 cells in a dose-dependent manner, and caused obvious cell apoptosis and a loss of DeltaPsi(m) in RAW264.7 cells. Moreover, the ROS production in cells was elevated, and the levels of activated caspase-3 and caspase-9 were up-regulated in a dose-dependent manner. Notably, GA-induced cell apoptosis was markedly inhibited by caspase inhibitors. These results suggest that GA-induced RAW264.7 cell apoptosis may be mediated via a caspase-dependent mitochondrial signaling pathway.
Animals
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Antineoplastic Agents, Phytogenic/*pharmacology
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Apoptosis/*drug effects
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Cell Line
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Cell Proliferation/*drug effects
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Dose-Response Relationship, Drug
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Gossypol/*analogs & derivatives/pharmacology
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Membrane Potential, Mitochondrial/*drug effects
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Mice
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Mice, Inbred BALB C
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Reactive Oxygen Species/*metabolism
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Signal Transduction/*drug effects