细胞增殖分化异常与肿瘤

细胞增殖(cell proliferation)是指细胞分裂和再生的过程,细胞通过分裂进行增殖,使遗传信息传给子代,保持物种的延续性和数量增多。细胞分化(cell differentiation)是指在细胞增殖时,子代细胞在形态、结构和生理功能上产生差异的过程,即同一来源的细胞通过细胞分裂增殖产生结构和功能上有特定差异的子代细胞,细胞分化的本质是细胞发生基因差别表达。     

抗坏血酸对人肝癌细胞增殖与再分化的作用

AIM: To examine the effects of ascorbic acid (AA) on hepatoma. METHODS: Choosing an all-trans tretinoin (Tre) as a positive control, cell growth, and cell redifferentiation tests by cell surface charges, biochemical changes, and cell growth in soft agar were measured. RESULTS: After being treated with AA 6 mmol.L-1, the growth curve and mitotic index of human hepatoma cells decreased remarkably, the cellular growth inhibitory rate amounted to 58.9%. The indices related with cell malignancy alleviated, such as cell surface charge obviously decreased, the electrophoresis rate dropped from 1.64 microns.s-1.V-1.cm-1 to 0.93, the average value of alpha-fetoprotein (alpha-FP) content decreased from 302 micrograms.g-1(protein) to 90, and gamma-glytamyl-transpeptidase (gamma-GT) activity from 0.81 U.g-1(protein) to 0.16. The index related with cell differentiation increased, such as the average level of tyrosine-alpha-ketoglutarate transminase activity increased from 10.3 micromol.g-1(protein) to 41.2, and the colonogenic potential decreased 94.4%. CONCLUSION: AA can inhibit human hepatoma cells proliferation, induce redifferentiation, and reverse its malignant phenotypic characteristics.     

板蓝根水提物对3T3-L1前脂肪细胞增殖和分化的影响

目的探讨板蓝根水提物(water extract of Radix Isatidis,WERI)对3T3-L1前脂肪细胞增殖分化的影响及其作用机制。方法体外培养3T3-L1前脂肪细胞,MTT法和流式细胞技术检测WERI对细胞增殖的影响;鸡尾酒诱导剂诱导3T3-L1前脂肪细胞,油红O染色和比色分析法观察WERI对前脂肪细胞分化及脂肪积累的影响;采用RT-PCR检测脂肪细胞的过氧化物酶体增殖物激活受体γ(peroxisome proliferator-activated receptorγ,PPARγ)及CCAAT/增强子结合蛋白α(CCAAT/enhancer-binding proteinα,C/EBPα)mRNA的表达;Western blot法检测PPARγ及C/EBPα蛋白表达。结果WERI在一定浓度范围内能有效抑制3T3-L1前脂肪细胞增殖,同时细胞周期呈现G_0/G_1向S期阻滞;与空白组相比,用不同浓度的WERI处理后,3T3-L1前脂肪细胞的分化受到明显抑制,且细胞内脂滴生成量明显减少;PCR及Western blot结果显示,WERI还可以抑制脂肪细胞PPARγ和C/EBPα基因及蛋白的表达。结论 WERI具有抑制3T3-L1前脂肪细胞增殖作用,并可通过下调PPARγ和C/EBPαmRNA及蛋白表达来抑制细胞成脂分化。     

小檗碱对3T3-L1前脂肪细胞增殖和分化的影响

脂肪细胞的增多是由于前脂肪细胞的不断分化引起。小檗碱是中药黄连的成分，具有改善胰岛素抵抗、降低血糖和调节血脂紊乱的作用，可用于治疗2型糖尿病，但它是否参与脂肪细胞的增殖和分化过程，目前尚不清楚。本研究通过小檗碱干预小鼠前脂肪细胞观察其对该细胞增殖和分化的影响，为肥胖的2型糖尿病的治疗提供可能的途径。     

肾上腺素对大鼠前脂肪细胞增殖、分化及其细胞内cAMP的影响

目的研究肾上腺素对大鼠前脂肪细胞增殖、分化及其细胞内cAMP水平的影响,探讨肾上腺素对大鼠前脂肪细胞的作用机制。方法原代培养大鼠前脂肪细胞,用四甲基偶氮唑盐(MTT)法检测六味地黄超微饮片含药血清对前脂肪细胞的增殖,以酶组织化学法检测其对前脂肪细胞分化过程中的磷酸甘油脱氢酶(GPDH)的影响,油红O染色方法测定其对细胞内脂肪积聚的影响。在大鼠前脂肪细胞生长旺盛时加入肾上腺素,以该细胞内的cAMP水平作为评价指标,利用cAMP与125I-cAMP和特异性蛋白激酶竞争结合原理测定该细胞内cAMP浓度。结果肾上腺素促进大鼠前脂肪细胞的增殖,抑制分化过程中GPDH的升高及脂肪积聚;升高大鼠前脂肪细胞内cAMP水平。结论肾上腺素-β受体-cAMP系统可能参与大鼠前脂肪细胞的增殖与分化。     

甲壳胺对人牙周膜细胞增殖和分化的影响

目的探讨甲壳胺对人牙周膜细胞增殖和分化功能的影响。方法用原代培养的人牙周膜细胞,采用MTT法、酶动力学法和放射免疫法检测不同浓度甲壳胺(Chitosan,Chi,0.05,0.1,0.2g·L-1)对人牙周膜细胞增殖、碱性磷酸酶活性和骨钙素分泌的影响。结果与对照组比较,(1)Chi(0.05g·L-1)和Chi(0.1g·L-1)2组在3,5,7d时A570值均明显升高(P<0.05),Chi(0.2g·L-1)组仅在3d时明显升高(P<0.01);(2)不论是细胞裂解液还是细胞培养液中,甲壳胺均能明显增强牙周膜细胞碱性磷酸酶活性(P<0.05);(3)不同浓度的甲壳胺刺激牙周膜细胞骨钙素分泌量均较对照组高,但只有Chi(0.1g·L-1)组比较有显著性差异(P<0.05)。结论甲壳胺对人牙周膜细胞的增殖和分化功能有明显的促进作用。     

硒化壳聚糖对HL60细胞增殖分化的影响

目的 探讨硒化壳聚糖与细胞c-myc和c-fos基因表达的关系及对人早幼粒白血病HL60细胞增殖和分化的影响.方法 采用SRB法和克隆形成法检测细胞增殖;Wright-Giemsa染色法检测细胞分化;流式细胞术检测CD11b、c-myc和c-fos分子表达.结果 25、50、100 mg/L硒化壳聚糖作用HL60细胞48 h可明显促进细胞分化和抑制细胞增殖(P＜0.05,P＜0.01);各浓度硒化壳聚糖均可使细胞CD11b蛋白表达显著升高(P＜0.01),c-myc蛋白表达下降(P＜0.05或P＜0.01),c-fos蛋白表达升高(P＜0.05或P＜0.01).结论 硒化壳聚糖可通过调控c-myc和c-fos基因表达来抑制HL60细胞增殖,促进细胞分化.     

RA联合IFN—γ诱导分化抑制胶质瘤细胞增殖的协同作用

目的 探索用维甲酸（ＲＡ）联合干扰素－γ（ＩＦＮ－γ）协同诱导分化治疗脑胶质瘤的新方案。方法 应用改良ＭＴＴ法,系统分析ＲＡ／ＩＦＮ－γ协同调控脑胶质瘤细胞增殖的量效、时效关系。结果 ＲＡ及ＩＦＮ－γ单独应用时,在药理可达浓度（分别为１０＾－６Ｍ及４０ＩＵ／ｍｌ）水平对体外培养的脑胶质瘤细胞具有一定的抑制增殖效应,但作用较弱;ＲＡ／ＩＦＮ－γ协同诱导分化治疗能有效逆转脑胶质瘤细胞的恶性增殖表型。     

吡格列酮衍生物CQMUHS-03对3T3-L1细胞增殖分化的影响

目的研究吡格列酮衍生物CQMUHS-03对3T3-L1细胞增殖及诱导分化的影响,为CQMUHS-03的临床应用提供理论基础。方法 (1)不同浓度药物处理细胞,于24、48、72h,MTT法检测CQMUHS-03对3T3-L1前脂肪细胞增殖的影响。(2)建立3T3-L1细胞诱导分化模型,药物处理后经油红O染色,拍照后并测定570 nm处光密度值以确定有效药物干预浓度。(3)Western blot测定药物对PPARγ蛋白表达的影响。(4)Real-time PCR分析PPARγ基因表达。结果(1)经24、48、72 h MTT检测,1×10-6mol·L-1浓度以下的CQMUHS-03对3T3-L1细胞增殖的抑制作用弱,IC50为3.33×10-4mol·L-1,高于吡格列酮(2.91×10-4mol·L-1)。(2)油红O染色测定结果显示吡格列酮促进3T3-L1前脂肪细胞分化,而CQMUHS-03对3T3-L1前脂肪细胞的分化促进作用不明显。(3)Real-time PCR检测显示诱导分化8 d,吡格列酮组PPARγmRNA表达上调5.12倍,CQMUHS-03组PPARγmRNA表达上调2.29倍。(4)Western blot结果显示,CQMUHS-03使PPARγ的表达增高。结论吡格列酮衍生物CQMUHS-03对3T3-L1细胞抑制增殖作用弱于吡格列酮,对细胞分化无明显促进作用,能上调PPARγ基因和蛋白表达。     

Neuropeptide Y receptors as targets for anti-obesity drug development: perspective and current status

Neuropeptide Y is a widely distributed neuropeptide that elicits a plethora of physiological effects via interaction with six different receptors (Y₁–y₆). Recent attention has focused on the role of neuropeptide Y in the regulation of energy homeostasis. Neuropeptide Y stimulates food intake, inhibits energy expenditure, increases body weight and increases anabolic hormone levels by activating the neuropeptide Y Y₁ and Y₅ receptors in the hypothalamus. Based on these findings, several neuropeptide Y Y₁ and Y₅ receptor antagonists have been developed recently as potential anti-obesity agents. In addition, mice lacking neuropeptide Y, the neuropeptide Y Y₁ receptor or the neuropeptide Y Y₅ receptor have been generated. The data obtained to date with these newly developed tools suggests that neuropeptide Y receptor antagonists, particularly neuropeptide Y Y₁ receptor antagonists, may be useful anti-obesity agents. However, the redundancy of the neurochemical systems regulating energy homeostasis may limit the effect of ablating a single pathway. In addition, patients in whom the starvation response is activated, such as formerly obese patients who have lost weight or patients with complete or partial leptin deficiency, may be the best candidates for treatment with a neuropeptide Y receptor antagonist.     

神经肽Y在雌性大鼠下丘脑的分布

目的　观察神经肽 Y(NPY)阳性神经元在下丘脑的分布 ,为探讨中枢 NPY神经元的功能提供形态学依据。方法　链霉素 -亲和素 -生物素复合物法 (SABC)。结果　在下丘脑的视上核、背内侧核、腹内侧核、弓状核均可见阳性神经元。在视上核 NPY阳性神经元较多 ,着色较深 ,胞体较大。结论　 NPY阳性神经元在下丘脑的视上核分布较广泛。     

Neuropeptide Y and energy homeostasis: insights from Y receptor knockout models

A complex system has evolved to regulate food intake and to maintain energy homeostasis. A series of short-term hormonal and neural signals that derive from the gastrointestinal tract, such as cholecystokinin (CCK), pancreatic polypeptide (PP) and peptide YY-(3–36), recently discovered to regulate meal size. Others such as ghrelin initiate meals, and insulin and leptin, together with circulating nutrients, indicate long-term energy stores. All these signals act on central nervous system sites which converge on the hypothalamus, an area that contains a large number of peptide and other neurotransmitters that influence food intake with neuropeptide Y (NPY) being one of the most prominent ones. Five Y receptors are known which mediate the action of neuropeptide Y and its two other family members, peptide YY and pancreatic polypeptide. Elevated neuropeptide Y expression in the hypothalamus leads to the development of obesity and its related phenotypes, Type II diabetes and cardiovascular disease. The limited availability of specific pharmacological tools and the considerable number of Y receptors have made it difficult to delineate their individual contributions to the regulation of energy homeostasis. However, recent studies analysing transgenic and knockout neuropeptide Y and Y receptor mouse models have started to unravel some of the individual functions of these Y receptors potentially also helping to develop novel therapeutics for a variety of physiological disorders including obesity.     

Neuropeptide Y and somatostatin immunoreactivity in the rat hippocampus after moderate hypoxia

Transient moderate hypoxia has been previously shown to exert a potent protective role to subsequently applied convulsant drugs. We now investigated neuropeptide Y and somatostatin immunoreactivities seven days after moderate hypoxia (9% O₂ in N₂ for two times 8 h) in the hippocampus of the rat. A slight reduction of somatostatin immunoreactive cells was observed in the hilus of the dorsal and ventral hippocampus. At the same time, the total number of neuropeptide Y immunoreactive neurons was increased in this area due to a pronounced increase in staining of presumable basket cells. There was also increased staining of neuropeptide Y positive fibers in the outer molecular layer. Our data suggest activation of neuropeptide Y containing interneurons after a moderate or a mild transient hypoxia. Activation of these inhibitory neurons may contribute to the protective effect of this treatment.     

血浆神经肽Y浓度变化与原发性高血压及靶器官损害的相关研究

目的探讨血浆神经肽Y(NPY)在原发性高血压发生发展中作用及对靶器官损害的临床意义。方法用放射免疫方法测定205例原发性高血压患者和45例健康人空腹静脉血NPY的血浆浓度。结果与对照组比较,原发性高血压患者血浆NPY浓度显著升高(P<0.05);原发性高血压患者血浆NPY浓度随血压升高显著升高(P<0.05);伴靶器官损害的高血压组比无靶器官损害的单纯高血压组血浆NPY浓度高(P<0.05);联合靶器官损害组比单一靶器官损害组血浆NPY浓度高(P<0.05)。结论神经肽Y可能参与了原发性高血压病的发生发展过程,其浓度高低与原发性高血压靶器官损伤程度相关。     

Neuropeptide Y administration into the third ventricle does not increase sucrose or ethanol self-administration but does affect the cortical EEG and increases food intake

RATIONALE: Several studies have provided indirect evidence that neuropeptide Y (NPY) may play a role in the regulation of ethanol consumption. However, the direct effects of central NPY administration on ethanol drinking are unclear. OBJECTIVE: This study examined the effects of NPY on ethanol, sucrose, and food consumption as well as its concomitant effects on the cortical EEG. METHODS: Wistar rats were implanted with cortical recording electrodes and a cannula in the third ventricle after using a sucrose substitution procedure to establish ethanol self-administration. NPY (0-15 microg/3.0 microl) was infused into the third ventricle prior to drinking sessions, when 10% ethanol (10E), 2% sucrose (2S), 0.5% sucrose (0.5S), or food were available. Behavior and cortical EEG were monitored during the sessions. RESULTS: NPY had no effect on the intake of 10E, 2S, or 0.5S, but NPY (15 microg/3.0 microl) significantly increased food intake. Under baseline drinking conditions, EEG power in the 6-8 Hz range was significantly greater when 2S was consumed compared to 10E. NPY decreased power in the 8-16 Hz range, decreased peak frequency in the 6-8 Hz range, and increased peak frequency in the 32-50 Hz range when 10E or 2S was available. CONCLUSIONS: These data suggest that NPY administration into the third ventricle preferentially regulates feeding compared to ethanol or sucrose drinking. In addition, since NPY significantly altered the cortical EEG in the absence of effects on ethanol and sucrose consumption, these data may indicate that NPY's cortical EEG effects are more related to its sedative or anxiolytic properties, rather than any effect on consumption.     

Orthogonal solid-phase synthesis of a monobiotinylated analog of Neuropeptide Y

Analogs of Neuropeptide Y (NPY) were synthesized with conventional Boc/benzyl protective group strategy. Instead of Asn⁷ in the native scquence, Boc-Lys(Alloc)-OH was incorporated. At the end of the synthesis the Alloc group was selectively removed by palladium-catalyzed hydrostannolysis and biotin coupled to the e-amino group of Lys⁷. After cleavage and characterization with plasma desorption mass spectrometry the N^e-7-biotinyl-[Lys⁷]-NPY and the nonbiotinylated analog [Lys⁷]-NPY were investigated as ligands to the NPY receptor from rat cerebral cortex. Both analogs were found to be high affinity ligands to the NPY receptor and bound with essentially the same affinity as unmodified NPY.     

丹红注射液对不稳定性心绞痛患者神经肽Y的影响

目的探讨不稳定性心绞痛（UAP）患者血浆神经肽Y（NPY）含量的变化，并观察丹红注射液对UAP患者神经肽Y（NPY）含量的影响。方法不稳定性心绞痛患者86例，随机分为对照组和实验组，对照组予以常规治疗，实验组在对照组的基础上加用丹红治疗。观察2组治疗前后血浆NPY的变化及疗效。结果不稳定性心绞痛患者发作期血浆NPY水平明显高于正常对照者（P〈0．01）。1周后应用丹红注射液治疗的不稳定性心绞痛组血浆NPY含量较未用丹红注射液治疗组下降明显（P〈0．05）。结论丹红注射液能有效地减轻NPY的缩血管作用，对改善UAP患者心肌供氧有重要作用。     

Neuroprotective Effects of Neuropeptide Y against Neurodegenerative Disease

Neuropeptide Y (NPY), a 36 amino acid peptide, is widely expressed in the mammalian brain. Changes in NPY levels in different brain regions and plasma have been described in several neurodegenerative diseases, including Alzheimer''s disease, Parkinson''s disease, Huntington''s disease, Amyotrophic Lateral Sclerosis, and Machado-Joseph disease. The changes in NPY levels may reflect the attempt to set up an endogenous neuroprotective mechanism to counteract the degenerative process. Accumulating evidence indicates that NPY can function as an anti-apoptotic, anti-inflammatory, and pro-phagocytic agent, which may be used effectively to halt or to slow down the progression of the disease. In this review, we will focus on the neuroprotective roles of NPY in several neuropathological conditions, with a particular focus on the anti-inflammatory properties of NPY.     

毛蕊花糖苷对新生大鼠体外培养成骨细胞增殖与分化作用研究

目的研究毛蕊花糖苷对体外培养新生大鼠颅骨成骨细胞(rat calvarial osteoblasts,ROB)增殖、分化作用的影响。方法采用Ⅱ型胶原酶消化法分离制备新生大鼠颅骨ROB细胞,MTT法测定ROB细胞增殖,碱性磷酸酶(ALP)试剂盒法测定ROB细胞内ALP活性,以细胞的增殖率和ALP活性作为考察指标,观察不同浓度的毛蕊花糖苷对ROB细胞增殖和分化作用的影响。结果 1×10-7～1×10-9mol·L-1的毛蕊花糖苷对ROB细胞的增殖具有显著的促进作用(P<0.05),且终浓度为1×10-7mol·L-1的毛蕊花糖苷在作用72h后能显著提高ROB细胞内碱性磷酸酶的活性(P<0.05)。结论一定浓度的毛蕊花糖苷能显著的促进ROB细胞的增殖和分化。