p38信号通路对腹膜间皮细胞p27kip1和纤连蛋白的影响

目的 探讨p38有丝分裂素激活蛋白激酶(MAPK)对高糖诱导的人腹膜问皮细胞(HPMC)p27^kip1的表达和纤连蛋白(FN)分泌的影响。方法 同步化生长融合的HPMC在有或无p38 MAPK抑制剂SB203580的条件下和不同浓度的葡萄糖共同孵育。采用Bradford法测定细胞内总蛋白量。采用逆转录．聚合酶链反应(RT．PCR)方法检测p27^kip1 mRNA的表达。p27^kip1和p38 MAPK蛋白用Western印迹法测定。采用酶联免疫吸附试验(ELISA)测定细胞培养液FN水平。结果 高糖刺激HPMC时细胞内总蛋白量、p27^kip1蛋白及细胞培养液里的FN蛋白水平明显升高。抑制p38 MAPK活性可有效阻断高糖介导的腹膜间皮细胞p27^kip1的表达及FN的分泌。结论 高糖通过p38 MAPK的活化可上调HPMC p27^kip1的表达和FN的分泌。     

P38MAPK 信号通路在高糖导致人腹膜间皮细胞 PARP -1激活、细胞外基质聚集及转分化的作用

目的：探讨人腹膜间皮细胞株 HMrSV5在高糖刺激下,P38MAPK 信号通路的活化情况及 PARP -1的蛋白表达情况。探讨 P38MAPK 抑制剂对腹膜间皮细胞外基质聚集及细胞转分化的作用及对 PARP -1的活性变化。方法：无血清培养 HMrSV5细胞株16~24 h 后,分别用高糖（终浓度138 mmol/ L 葡萄糖）刺激0 m、5 m、30 m、1 h、2 h、8 h、24 h,并选择等渗的甘露醇作为对照用。Western Blot 分别检测不同时间总的 P38MAPK 及磷酸化的 P38MAPK 的蛋白表达水平。同时用Western blot 检测在不同时间点 PARP -1的蛋白表达情况。无血清培养 HPMCs16~24 h 后,分为4各组：（1）低糖组（5．6 mmol/ L 葡萄糖）;（2）刺激组（138 mmol/ L 葡萄糖）;（3）抑制剂组（138 mmol/ L 葡萄糖＋ SB203580P38抑制剂,浓度为10μmol/ L）;（4）DMSO 对照组。在24 h 收取细胞用 Western blot 检测 P38MAPK、PARP -1、FN、PAI -1、E - cadherin 及α-SMA 的蛋白水平变化。结果：高糖以时间依赖的方式刺激 HPMCs 后,磷酸化的 P38MAPK 表达增加。PARP -1的表达在高糖刺激下也呈时间依赖性增高,24 h 已很明显。用 P38MAPK 抑制剂 SB203580后,PARP -1及 FN、PAI -1及α- SMA 也下调,E - cadherin 表达上调,差异有统计学意义（P 〈0．05）。结论：高糖可使得人腹膜间皮细胞 P38MAPK 通路的活化。运用P38的抑制剂,均能使得 PARP -1活性下调,同时逆转腹膜间皮细胞外基质聚集及 HPMCs 转分化。这提示在高糖刺激腹膜间皮细胞时,P38MAPK 参与了 PARP -1的活化,并参与腹膜间皮细胞外基质聚集及人腹间皮细胞转分化。     

色素上皮衍生因子对高糖诱导人肾小球系膜细胞p38丝裂原活化蛋白激酶-cAMP反应元件结合蛋白通路及纤连蛋白的影响

目的 探讨色素上皮衍生因子(PEDF)对高糖条件下人肾小球系膜细胞( HMC )p38丝裂原活化蛋白激酶(p38MAPK)、cAMP反应元件结合蛋白(CREB)及细胞外基质成分纤连蛋白(FN)的影响.方法 体外予正常糖(5.6 mmol/L)、甘露醇(24.4 mmol/L)、高糖(30 mmol/L)、高糖+PEDF(30 mmol/L葡萄糖+10 nmol/L、40 nmol/L、100 nmol/L PEDF)培养基培养HMC 24 h,观察p38MAPK、CREB活性(Western印迹)及FN mRNA( RT-PCR)和蛋白( ELISA)的变化.结果 与正常糖及甘露醇组相比,高糖组p-p38MAPK、p-CREB、FN的表达均显著升高(均P＜ 0.01);与高糖组相比,PEDF干预组上述指标的表达均显著下降(均P＜0.05).结论 PEDF可能通过p38MAPK-CREB通路抑制糖尿病肾病的纤维化.     

Chemerin/ChemR23 promotes high glucose-induced IL-6 and TNF-α expressions in glomerular endothelial cells via p38 MAPK

Objective To observe the role and related mechanism of chemerin and its receptor ChemR23 in glomerular endothelial cells (GEnCs) stimulated by high glucose. Methods Mouse GEnCs were cultured and divided into control group, 20.0 mmol/L high glucose group, 40.0 mmol/L high glucose group and mannitol control group. Then the expressions of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in cell culture supernatant as well as the expressions of intracellular protein and mRNA of chemerin, ChemR23, IL-6 and TNF-α were detected. Lentiviral transfection targeting ChemR23 was applied before high glucose- or Chemerin-stimulated, and expressions of supernatant and intracellular mRNA of IL-6 and TNF-α were measured. Meanwhile whether p38 mitogen-activated protein kinase (p38 MAPK) pathway was activated by high glucose was detected. The specific inhibitor of p38 MAPK was added prior to high glucose-stimulated, then supernatant and intracellular mRNA expressions of IL-6 and TNF-α was detected. The supernatant expressions of IL-6 and TNF-α were measured by ELISA. The intracellular protein expression and p38 MAPK phosphorylation activity were detected by Western blotting. The mRNA expression was detected by real time PCR. Results Compared with those in the control group, in high glucose groups the expressions of IL-6, TNF-α and chemerin were significantly increased (all P＜0.05), however, the expressions of ChemR23 did not change (all P＞0.05); the supernatant and mRNA expressions of IL-6 and TNF-α were also elevated in the chemerin group (all P＜0.05). Lentivirus baring shRNA could efficiently suppress ChemR23 expression, and the Chemerin- or high glucose-induced expressions of IL-6 and TNF-α were reduced (all P＜0.05). Also it could significantly reduce the expression of phosphorylated-p38 MAPK (p-p38 MAPK) induced by high glucose (P＜0.05), as high glucose group had higher p-p38 MAPK than control group (P＜0.05). While the high glucose-elevated expressions of IL-6 and TNF-α were significantly attenuated by p38 MAPK inhibitor (all P＜0.05). Conclusions High glucose stimulation can induce the expression of chemerin in GEnCs. By binding to ChemR23, chemerin activates p38 MAPK signaling pathway, and then promotes the expressions of IL-6 and TNF-α. These inflammatory cytokines aggravate inflammation of GEnCs.     

Global adiponectin suppress the high expression of monocyte chemotactic protein-1 induced by high glucose in NRK52E cells

Objective To investigate the effect of globular adiponectin on the high expression of monocyte chemotactic protein-1 (MCP-1) induced by high glucose in rat renal tubular epithelial cells(NRK52E), and its relationship with adiponectin receptors and p38MAPK. Methods NRK52E cells were cultured in vitro and divided into six groups: normal glucose group (NG, 5.6 mmol/L glucose), high glucose group(HG, 25 mmol/L glucose), gAd group1 (HG+gAd 2 mg/L), gAd group2 (HG+gAd 5 mg/L), gAd group3 (HG+gAd 10 mg/L), p38MAPK antagonist group：(SB, HG+SB203580 10 μmol/L). The protein expression of phosphorylated p38MAPK (p-p38MAPK), total p38MAPK (t-p38MAPK), MCP-1 and AdipoR1/AdipoR2 were examined by western blotting. The mRNA expression of MCP-1 and AdipoR1/AdipoR2 were detected by RT-PCR and real-time PCR respectively. Results Compared with NG group, the mRNA and protein expression of MCP-1 increased significantly in HG group (all P＜0.05). The phosphorylation of p38MAPK increased (P＜0.05) with no change in t-p38MAPK protein. The addition of gAd or SB203580 inhibited the unregulation of MCP-1 and p-p38MAPK induced by HG. Two kinds of adipoR,adipoR1 and adipoR2,were all detectable in NG group, and mRNA and protein expression of adipoR1 was higher than that of adipoR2 (P＜0.01). Compared with NG group, the expression of adipoR decreased in HG group, but the difference had no statistical significance(P＞0.05). Compared to HG group, the mRNA and protein expression of adipoR1 increased in gAd groups (all P＜0.01). Conclusion The gAd can dose-dependently attenuate the overexpression of MCP-1 induced by high glucose, and this protective effect may be mediated by adipoR1 and p38MAPK.     

Low-density lipoprotein promotes epithelial-mesenchymal transition and extracellular matrix accumulation in human peritoneal mesothelial cells

Objective To investingate the effect of low-density lipoprotein (LDL) on epithelial-mesenchymal transition and extracellular matrix (ECM) accumulation in human peritoneal mesothelial cells (HPMCs). Methods (1)HPMCs were randomly divided into control group, LDL group (100 mg/L) and LDL (100 mg/L)＋lactoferrin (100 mg/L, LDL receptor blocking agent) group. After co-cultured for 24 h, the expression of LDL receptor in HPMCs was examined by immunofluorescence staining, and the LDL uptake by HPMCs was observed with oil red O staining. (2)HPMCs were cultured with different concentrations of LDL (0, 25, 50, 100 mg/L). After co-cultured for 24 h, the change of cell morphology was observed by inverted phase contrast microscope, and the expression of α-smooth muscle actin (α-SMA) was examined by immunofluorescence. (3) HPMCs were randomly divided into control group (5.6 mmol/L glucose), mannitol group (M, 2.18% mannitol), low glucose group (LG, 30 mmol/L), high glucose group (HG, 120 mmol/L) and HG＋LDL group (120 mmol/L glucose＋100 mg/L LDL). Co-cultured for 48 h, the mRNA expression of α-SMA, E-cadherin and type 1 plasminogen activator inhibitor (PAI-1) was detected by real-time quantitative PCR, the protein expression of α-SMA was detected by Western blotting, the content of type I collagen (ColⅠ) and PAI-1 in supernatant was detected by ELISA. Results (1) After co-cultured with LDL for 24 h, the expressin of LDL receptor was found on the cell membrane of HPMCs. Oil red staining showed that LDL could be uptaken into the cells and abolished by LDL receptor blocker. (2) HPMCs tended to be loosely intercellular connected to each ofher, and prsesnted significant formation of fibroblast?like spindle morphology. The cytoplasm immunofluorescence intensity of α-SMA gradually increased with the increase of LDL concentration. Compared to the control group, the expressions of α-SMA mRNA and protein were significantly increased, and the expression of E-cadherin mRNA was decreased in HG＋LDL group(all P＜0.05). But the expressions of the parameters above-mentioned were not significant different between HG group and HG＋LDL group or between HG group and control group. (3) Compared with HG group or control group, the concentrations of ColⅠ[(19.27±0.17) μg/L vs (14.09±0.30) μg/L or (14.81±0.91) μg/L, all P＜0.05] and PAI-1 [(498.24±76.91) ng/L vs (342.19±30.43) ng/L or (220.39±33.82) ng/L, all P＜0.05] in supernatant of HPMCs were significantly up-regulated in HG＋LDL group, meanwhile the expression of PAI-1 mRNA was significantly higer than that in control group (P＝0.022）. Conclusions HPMCs uptake LDL into cells via LDL receptors. LDL can induce HPMCs transdifferentiation in the condition of high glucose, increase the secretion of ColⅠ, inhibit the degradation of ECM through up-regulating the expression of PAI-1, and lead to ECM accumulation.     

TAK1信号通路在高糖诱导骨髓来源巨噬细胞激活中的作用

Objective To investigate the role of transforming growth factor-β activated kinase-1 (TAK1) signaling pathway in the activation of bone marrow derived macrophages (BMDM) induced by high glucose. Methods Purity of mouse BMDM was detected by flow cytometry. The mice macrophages cultured in vitro were stimulated by high glucose and treated with TAK1 specific inhibitor 5Z-7-oxozeaenol. Cells were divided into normal control group (RPMI 1640), osmolality control group (25 mmol/L mannitol), high glucose group (33 mmol/L D-glucose) and inhibitor group (33 mmol/L D-glucose+300 nmol/L 5Z-7-oxozeaenol). Immunocytochemistry and flow cytometry were used to detect macrophage subtype. The expression of monocyte chemotactic protein-1 (MCP-1) and tumor necrosis Factor-α (TNF-α) mRNA were determined by real time PCR. Expressions of p-TAK1, TAK1 binding protein (TAB1), p-JNK, p-p38 MAPK and NF-κB p65 proteins were analyzed by Western blotting. Results The purity of BMDM was about 99.36%. Compared with normal control group, high glucose group had increased percentage of M1 macrophages, increased expression of MCP-1 and TNF-α mRNA (all P＜0.05). Moreover, p-TAK1, TAB1, p-JNK, p-p38 MAPK and NF-κB p65 proteins expression also increased significantly in high glucose group (all P＜0.05). After treatment with inhibitor 5Z-7-oxozeaenol, the effects induced by high glucose were inhibited (P＜0.05). Conclusions High glucose can induce M1 macrophage activation and expression of inflammatory cytokine of BMDM, which can be inhibited 5Z-7-oxozeaenol through inhibiting TAK1/MAPK and TAK1/NF-κB pathway.     

High glucose decreases collagenase expression and increases TIMP expression in cultured human peritoneal mesothelial cells.

BACKGROUND: Peritoneal fibrosis (PF), a serious problem in long-term continuous ambulatory peritoneal dialysis (CAPD) patients, is characterized by extracellular matrix (ECM) accumulation which results from an imbalance between the synthesis and the degradation of ECM components. Previous studies have demonstrated that ECM synthesis is increased in human peritoneal mesothelial cells (HPMCs) under high glucose conditions, but the effects of high glucose on degradative pathways have not been fully explored. This study was undertaken to elucidate the effects of high glucose on these proteolytic processes in cultured HMPCs. METHODS: HPMCs were isolated from human omentum and were exposed to 5.6 mM glucose (NG), 5.6 mM glucose +34.4 mM mannitol (NG + M), or 40 mM glucose (HG) with or without PKC inhibitor (PKCi). Real-time PCR and western blot were performed to determine collagenases (MMP-1, -8 and -13) and TIMPs (TIMP-1 and -2) mRNA and protein expression, respectively. The individual activities of collagenases in culture media were determined by ELISA. RESULTS: Types I and III collagen protein expression were significantly increased in HG-conditioned media compared to NG media (P < 0.05). The MMP-1, -8 and -13/GAPDH mRNA ratios were significantly lower in HPMCs exposed to HG medium compared to NG cells by 64, 52 and 37%, respectively, and their protein expression by 76, 42 and 49%, respectively, in HG- vs NG-conditioned media. The activities of collagenases in HG-conditioned media were also significantly lower than those in NG media (P < 0.05). In contrast, HG significantly increased TIMPs mRNA ratios and protein expression in HPMCs. These changes in collagenase and TIMP expression induced by HG were abrogated upon pre-treatment with PKCi. CONCLUSION: In conclusion, impaired matrix degradation may contribute to ECM accumulation in PF.     

Ursolic acid inhibits high glucose-induced epithelial mesenchymal transition of podocyte by mediating Wnt/β-catenin signaling pathway

Objective To observe the epithelial mesenchymal transition (EMT) of podocyte induced by high glucose, and to explore the potential protective mechanism of ursolic acid (UA). Methods The podocytes cultured in vitro were divided into four groups: normal group (glucose 5.5 mmol/L), mannitol group (glucose 5.5 mmol/L+mannitol 19.5 mmol/L), high glucose group (glucose 25 mmol/L) and UA group (glucose 25 mmol/L+UA 5 μmol/L). Podocyte morphology changes were observed by inverted phase contract microscope. The expression of zonula occludens-1 (ZO-1) and α-smooth muscle actin (α-SMA) were detected by immunofluorescence. The expressions of β-catenin and glycogen synthesis kinase-3β (GSK3β) were detected by Western blotting. The expressions of Wnt1, Wnt3a, Wnt5a, Wnt5b and GSK3β were detected by real-time PCR. Results Podocytes showed irregular arborization shape in normal glucose and transited to longer cobblestone-like shape as mesenchyme cell by high glucose culture. Compared with normal group, the expression of ZO-1 protein was down-regulated and the expression of α-SMA was up-regulated by high glucose culture (P＜0.05). The expression of Wnt5a mRNA was down-regulated; β-catenin mRNA and protein were up-regulated (P＜0.05); and GSK3β protein was down-regulated by high glucose culture (P＜0.05). Compared with high glucose group, ursolic acid inhibited podocyte EMT, up-regulated the expression of ZO-1 protein, Wnt5a mRNA, GSK3β (P＜0.05), and down-regulated the expressions of α-SMA protein, β-catenin mRNA and protein (P＜0.05). Conclusion Ursolic acid attenuates high glucose induced epithelial mesenchymal transition of podocyte by inhibiting Wnt/β-catenin signaling pathway.     

Involvement of TGF-beta signal for peritoneal sclerosing in continuous ambulatory peritoneal dialysis

BACKGROUND: Functional failure of the peritoneal membrane is the most serious problem in long-term continuous ambulatory peritoneal dialysis (CAPD). Transforming growth factor-beta (TGF-ss) is one of the key mediators of fibrosis in some organs, and is thought to be involved in peritoneal alterations. In this study, we examined the role of TGF-beta1/TGF-ss receptors for human peritoneal mesothelial cells (HPMCs) and fibroblasts, and their interactions in CAPD patients. METHODS: HPMCs were cultured for 48 h in a medium containing normal- dose glucose (7 mM), high-dose glucose (30 mM) and mannitol as an osmotic agent, equal to 30 mM glucose. Cell proliferation was observed using the Tetra Color One assay. The concentration of TGF-beta1 in culture supernatants was measured by enzyme-linked immunosorbent assay (ELISA). The expression of TGF-ss receptor types I and II was observed by flow cytometry. HPMCs and fibroblasts were co-cultured and assayed using transwell inserts in order to identify the effects of the high-concentration glucose solution. RESULTS: HPMC proliferation was inhibited by the high concentration of glucose but not by mannitol. The inhibition was abrogated by the neutralizing antibody for TGF-beta1. TGF-beta1 was induced by a high concentration of glucose but not by mannitol. The expression of both TGF-ss receptors was augmented in culture with the high concentration of glucose but not with mannitol. In the co-culture assay, the number of HPMCs was decreased and fibroblasts were significantly increased in culture with the high concentration of glucose. CONCLUSIONS: A high concentration of glucose induced a large amount of TGF-beta1 and enhanced the expression of TGF-ss receptors. HPMCs were sensitive to TGF-beta1 in response to a high concentration of glucose. These data suggest that TGF-beta1 from HPMCs exposed to a high concentration of glucose down-regulates the proliferation of HPMCs and accelerates peritoneal fibrosis.     

High glucose promotes human glomerulus mesangial cells senescence through activating p53/p21 pathways and suppressing autophagy

Objective To observe the changes of senescence and autophagy in human glomerulus mesangial cells (HGMCs) induced by high glucose at different times, and to investigate the effects of rapamycin and 3-methyladenine (3-MA) on these changes. Methods HGMCs were cultured in vitro, exposed to high glucose (30.0 mmol/L glucose) for 12, 24, 48 and 72 h, and stimulated by high glucose with 500 nmol/L rapamycin or 2 mmol/L 3-MA for 72 h. Normal control group (5.5 mmol/L glucose) and hypertonic group (5.5 mmol/L glucose + 24.5 mmol/L mannitol) were set up. Cytomorphology changes were examined by light microscope to test whether cells were in senescent stage. The quantity of autophagosome was observed by electron microscope. The cell senescence was evaluated by β-galactosidase (SA β-gal) staining. The protein expressions of p53, p21, LC3 and p62 were determined by Western blotting. Results High glucose group gradually had larger size and more flat cytoplasm, polymorphonuclear cells and binucleate cells than control group as the stimulation times was prolonged. Compared with those in control group, SA β-gal positive cells in high glucose group after incubation for 72 h statistically were increased (P＜0.05); the protein expressions of p62, p53 and p21 in high glucose group after incubation for 48 h and 72 h were increased (all P＜0.05), while the autophagosome and the expression of LC3 decreased (P＜0.05). Compared with those in high glucose group, the expression of LC3 was increased dramatically in high glucose with rapamycin group (P＜0.05), while the protein expressions of p62, p53 and p21 decreased (all P＜0.05), and SA β-gal positive cells decreased (P＜0.05). However, there was no statistical difference between high glucose group and high glucose with 3-MA group in terms of above effects. Conclusions High glucose may induce HGMCs senescence through activating p53/p21 pathways and suppressing the activity of autophagy. Through enhanced autophagy activity with rapamycin, the expression of p53/p21 pathway was suppressed and senescence was relieved.     

低盐诱导的致密斑细胞环氧化酶2表达与p38丝裂素激活蛋白激酶信号通路

目的 探讨低盐(LS)培养对小鼠致密斑细胞 (MMDD1)环氧化酶2 (COX-2)表达、前列腺素E2(PGE2)释放的诱导作用及p38丝裂素激活蛋白激酶(MAPK)信号通路的调控作用。方法 采用RT-PCR和免疫印迹方法检测正常盐(NS)与LS培养对MMDD1细胞COX-2表达的影响。用ELISA法检测上清液PGE2的含量。用免疫印迹检测细胞内p-p38 MAPK表达的变化。 结果 与NS培养相比,LS培养均能诱导MMDD1细胞COX-2 mRNA和蛋白表达增加(16 h时高峰 mRNA 0.94±0.12比0.26±0.09,28 h时高峰蛋白0.59±0.02比0.25±0.07,P均< 0.01);PGE2分泌各时间点均显著升高,于24 h达高峰 [(644.33±26.54)ng/L比(224.0±18.33)ng/L, P < 0.01。LS培养后,MMDD1细胞内p38MAPK的磷酸化程度显著上调,180 min时较高(从0.17±0.01升至0.28±0.01,P < 0.01)。20 μmol/L p38抑制剂SB-203580下调 LS诱导的COX-2蛋白表达(从0.58±0.01降至0.19±0.02, P < 0.01)。 结论 低盐培养促进MMDD1细胞COX-2的表达和PGE2的分泌。p38 MAPK激活介导了低盐诱导的MMDD1细胞COX-2表达。     

缬沙坦对高糖上调系膜细胞细胞外调节蛋白激酶表达的影响

目的观察在高糖刺激下，系膜细胞细胞外调节蛋白激酶（ERKI／2）的活性变化以及缬沙坦对其影响，探讨缬沙坦保护肾脏作用的可能机制。方法原代培养大鼠肾脏系膜细胞，随机分为4组：低糖组（NG，d-葡萄糖5．5mmol／L）、高糖组（HG，d-葡萄糖30mmol／L）、甘露醇组（MG，d-葡萄糖5．5mmol／L＋甘露醇24．5mmol／L）和缬沙坦组（HG＋Val，d-葡萄糖30mmol／L＋缬沙坦10μmol／L）。用免疫细胞化学法及Western印迹法对系膜细胞中磷酸化ERK1／2（p-ERK1／2）的表达进行定位及半定量分析；RT—PCR法检测细胞中TGF-β1 mRNA的表达；放射免疫法测定各组细胞上清中Ⅳ型胶原的含量。结果高糖组系膜细胞中P-ERK1／2蛋白的表达较低糖组明显增高，并由胞质向胞核内转移，呈时间依赖方式（P〈0．01）；TGF-β1 mRNA及细胞上清液中Ⅳ型胶原水平均高于低糖组（P〈0．01）。而缬沙坦组上述指标均较同时相点高糖组显著降低，差异有统计学意义（P〈0．01）。甘露醇组与低糖组各指标间差异均无统计学意义。结论高糖可显著激活系膜细胞ERK信号通路，缬沙坦可抑制高糖的激活作用。     

Transient high glucose induces persistent inflammatory status in rat glomerular mesangial cell via histone methylation modification

Objective To investigate whether the effect of transient high glucose on inflammatory factors expression could be continuous in rat glomerular mesangial cell, and its relation with histone methylation modification. Methods Rat glomerular mesangial cells (HBZY-1) were divided into three groups: the high glucose group (25.0 mmol/L glucose), the hypertonic group (MA, 5.5 mmol/L glucose+19.5 mmol/L mannitol) and the normal-glucose control group (5.5 mmol/L glucose), which were cultured for 24 h respectively. All 3 groups were then changed with normal-glucose medium to culture for 24 h, 48 h and 72 h. Their protein, mRNA and supernatant were harvested. The protein expressions of mono-methylation of H3 lysine 4 (H3K4me1) was measured by Western blotting, and the mRNA expressions of NF-κB subunit p65 and set7/9 were determined by real time-quantitative PCR. The expression of monocyte chemoattractant protein 1 (MCP-1) and vascular cell adhesion molecule 1 (VCAM-1) were detected by enzyme-linked immunosorbent assay. Results (1) Compared with those in normal control group, the expressions of H3K4me1 protein and set7/9 mRNA were first up-regulated in high glucose group, then gradually down-regulated in the following 48 h normal-glucose medium (as compared with those at 0 h, all P＜0.05). At 72 h there was no statistic difference between high glucose group and normal control group (all P＞0.05). (2) Compared with those in normal control group, the up-regulated p65 mRNA, VCAM-1 and MCP-1 sustained at least for 72 h in high glucose group. Conclusions Transient high glucose can induce persistent inflammatory factors expression in rat glomerular mesangial cells, which may via histone modification.     

活性氧与高糖对人腹膜间皮细胞增殖的影响

目的 研究不同浓度葡萄糖、活性氧(过氧化氢)、抗氧化剂对人腹膜间皮细胞(HPMC)细胞增殖的影响及其机制。方法用^3H-胸腺嘧啶(TdR)掺人法测定细胞增殖；用流式细胞仪检测细胞周期的改变；用半定量RT-PCR检测细胞周期调控蛋白p27^kip1mRNA水平；用细胞免疫组化方法和蛋白印迹(Western blotting)的方法检测p27^kip1蛋白水平。结果 高糖及较大剂量的过氧化氢(0．5mmol／L)均可以抑制HPMC增殖，而细胞周期分析提示细胞停滞于G1期。高糖加过氧化氢，则增加了后者的毒性作用。高糖及外源性过氧化氢均可以增加p27^Kip1蛋白表达。高糖加抗氧化剂，可以改善细胞周期停滞、增殖抑制作用，但p27^kip1的表达未见明显改变。结论 高糖及外源性过氧化氢均可通过增加p27^KiP1的表达使细胞周期发生停滞，从而抑制增殖。而高糖的增殖抑制作用还与内源性的活性氧有关，提示临床上抗氧化治疗可能有益。