Therapeutic potency of pharmacological adenosine receptor agonist/antagonist in angiogenesis,current status and perspectives

Objectives

Adenosine concentration significantly increases in tumour microenvironment contributing to tumorigenic processes including cell proliferation, survival, invasion and of special interest in this review angiogenesis.

Key findings

This review summarizes the role of pharmacological adenosine receptor agonist and antagonist in regulating angiogenesis for a better understanding and hence a better management of angiogenesis‐associated disorders.

Summary

Depending upon the pharmacological characteristics of adenosine receptor subtypes, adenosine elicits anti‐ or pro‐angiogenic responses in stimulated cells. Inhibition of the stimulatory effect of adenosine signalling on angiogenesis using specific pharmacological adenosine receptor agonist, and antagonist is a potentially novel strategy to suppress angiogenesis in tumours.

     

Can we increase the speed and efficacy of antidepressant treatments? Part II. Glutamatergic and RNA interference strategies

In the second part we focus on two treatment strategies that may overcome the main limitations of current antidepressant drugs. First, we review the experimental and clinical evidence supporting the use of glutamatergic drugs as fast-acting antidepressants. Secondly, we review the involvement of microRNAs (miRNAs) in the pathophysiology of major depressive disorder (MDD) and the use of small RNAs (e.g.., small interfering RNAs or siRNAs) to knockdown genes in monoaminergic and non-monoaminergic neurons and induce antidepressant-like responses in experimental animals.The development of glutamatergic agents is a promising venue for antidepressant drug development, given the antidepressant properties of the non-competitive NMDA receptor antagonist ketamine. Its unique properties appear to result from the activation of AMPA receptors by a metabolite [(2 S,6 S;2 R,6 R)-hydroxynorketamine (HNK)] and mTOR signaling. These effects increase synaptogenesis in prefrontal cortical pyramidal neurons and enhance serotonergic neurotransmission via descending inputs to the raphe nuclei. This view is supported by the cancellation of ketamine's antidepressant-like effects by inhibition of serotonin synthesis.We also review existing evidence supporting the involvement of miRNAs in MDD and the preclinical use of RNA interference (RNAi) strategies to target genes involved in antidepressant response. Many miRNAs have been associated to MDD, some of which e.g., miR-135 targets genes involved in antidepressant actions. Likewise, SSRI-conjugated siRNA evokes faster and/or more effective antidepressant-like responses. Intranasal application of sertraline-conjugated siRNAs directed to 5-HT_1A receptors and SERT evoked much faster changes of pre- and postsynaptic antidepressant markers than those produced by fluoxetine.     

Human adenosine deaminase 2 deficiency: A multi‐faceted inborn error of immunity

Human adenosine deaminase 1 deficiency was described in the 1970s to cause severe combined immunodeficiency. The residual adenosine deaminase activity in these patients was attributed to adenosine deaminase 2. Human adenosine deaminase type 2 deficiency (DADA2), due to biallelic deleterious mutations in the ADA2 gene, is the first described monogenic type of small‐ and medium‐size vessel vasculitis. The phenotype of DADA2 also includes lymphoproliferation, cytopenia, and variable degrees of immunodeficiency. The physiological role of ADA2 is still enigmatic hence the pathophysiology of the condition is unclear. Preliminary data showed that in the absence of ADA2, macrophage differentiation is skewed to a pro‐inflammatory M1 subset, which is detrimental for endothelial integrity. The inflammatory phenotype responds well to anti‐TNF therapy with etanercept and that is the first‐line treatment for prevention of severe vascular events including strokes. The classic immunosuppressive drugs are not successful in controlling the disease activity. However, hematopoietic stem cell transplantation (HSCT) has been shown to be a definitive cure in DADA2 patients who present with a severe cytopenia. HSCT can also cure the vascular phenotype and is the treatment modality for patients’ refractory to anti‐cytokine therapies. In this review, we describe what is currently known about the molecular mechanisms of DADA2. Further research on the pathophysiology of this multifaceted condition is needed to fine‐tune and steer future therapeutic strategies.     

尼拉帕尼：聚腺苷二磷酸-核糖聚合酶抑制剂

尼拉帕尼（Niraparib,商品名Zejula^TM）是聚腺苷二磷酸-核糖聚合酶（PARP）的口服小分子抑制剂,PARP抑制是治疗由DNA修复基因（如BRCA1和BRCA2）特异性畸变引起的DNA修复机制缺陷的癌症的有效策略。尼拉帕尼于2017年3月在美国获批,维持治疗复发性上皮性卵巢癌、输卵管癌、原发性腹膜癌的成年患者,这些患者对铂类化疗有完全或部分反应,推荐剂量为口服300 mg/d,直到疾病发生恶化或产生无法接受的不良反应。临床研究结果表明该药可以延长患者的无恶化生存期,为治疗卵巢癌提供了有效和可靠的治疗手段。     

连豆清脉颗粒对日本大耳白兔AS斑块的干预作用及对PARP-1的影响

目的:研究连豆清脉颗粒对日本大耳白兔动脉粥样硬化(AS)斑块的干预作用及多聚二磷酸腺苷核糖聚合酶-1(poly adenosine diphosphate ribose polymerase-1,PARP-1)的影响。方法:取健康清洁级雄性日本大耳白兔40只,随机抽取8只日本大耳白兔为空白组,以标准饲料喂养。其余32只日本大耳白兔采用高脂饲料喂养及牛血清白蛋白静脉注射建立AS斑块模型,成功建模的兔按照随机数字表,随机分成高脂组11只(实验过程中死亡2只)、连豆清脉方组8只,辛伐他汀组8只,分别予以高脂、连豆清脉方药物、辛伐他汀药物饲料喂养,给药剂量为辛伐他汀1 mg·kg~(-1)·d~(-1),连豆清脉方3.7 g·kg~(-1)·d~(-1),8周后,检测兔AS斑块面积,PARP-1阳性表达及Toll样受体-4(Toll like receptor-4,TLR-4)mRNA,核转录因子-κB(nuclear factor kappa-B,NF-κB),血清白细胞介素-6(interleukin-6,IL-6)水平。结果:空白组没有出现AS斑块,连豆清脉方组AS斑块明显,但是明显低于高脂组;与空白组比较,连豆清脉方组主动脉AS斑块面积比例,组织PARP-1阳性细胞表达率,TLR-4 mRNA表达,NF-κB及IL-6水平均显著升高(P0.01)。与高脂组比较,连豆清脉方组主动脉AS斑块面积比例,组织PARP-1阳性细胞表达率,TLR-4 mRNA表达,NF-κB及IL-6水平显著下降(P0.01)。结论:连豆清脉方可抑制AS斑块的增生;其机制可能与抑制PARP-1表达等炎症反应有关。     

The role of cyclic-AMP on arginase activity by a murine macrophage cell line (RAW264.7) stimulated with lipopolysaccharide from Actinobacillus actinomycetemcomitans

AIMS: The aim of the present study was to determine the role of cyclic adenosine monophosphate (cAMP) on arginase activity in a murine macrophage cell line (RAW264.7 cells) stimulated with lipopolysaccharide (LPS) from Actinobacillus actinomycetemcomitans. MATERIALS AND METHODS: The cells were treated with A. actinomycetemcomitans LPS for 24 h. The effects of SQ22536 (an adenylyl cyclase inhibitor), ODQ (a guanylyl cyclase inhibitor), dibutyryl cAMP (a cAMP analog), 8-bromo cyclic guanosine monophosphate (a cGMP analog), forskolin (an adenylyl cylase activator), and cycloheximide (a protein synthesis inhibitor) on arginase activity in A. actinomycetemcomitans LPS-stimulated RAW264.7 cells were also determined. Arginase activity was assessed in LPS-stimulated cells in the presence of 3-isobutyl-1-methylxanthine (IBMX), siguazodan and rolipram [phosphodiesterase (PDE) inhibitors] as well as KT5720 [a protein kinase A (PKA) inhibitor]. RESULTS: Arginase activity in A. actinomycetemcomitans LPS-stimulated RAW264.7 cells was suppressed by SQ22536 but not ODQ. Enhancement of arginase activity was observed in the presence of cAMP analog or forskolin but not cGMP analog. Cycloheximide blocked arginase activity in the cells in the presence of cAMP analog or forskolin with or without A. actinomycetemcomitans LPS. IBMX augmented arginase activity in A. actinomycetemcomitans LPS-stimulated cells. Rolipram (a PDE4 inhibitor) increased the levels of arginase activity higher than siguazodan (a PDE3 inhibitor) in the antigen-stimulated cells. The effect of cAMP analog or forskolin on arginase activity in the presence or absence of A. actinomycetemcomitans LPS was blocked by the PKA inhibitor (KT5720). CONCLUSION: The results of the present study suggest that A. actinomycetemcomitans LPS may stimulate arginase activity in murine macrophages (RAW264.7 cells) in a cAMP-PKA-dependent pathway.     

Conditioned-medium of stem cells from human exfoliated deciduous teeth prevent apoptosis of neural progenitors

PurposeThis study aimed to evaluate the neuroprotective ability of the conditioned medium of stem cells from human exfoliated deciduous teeth (CM-SHED) to prevent glutamate-induced apoptosis of neural progenitors.Materials and methodsNeural progenitors were isolated from two-day-old rat brains, and the conditioned medium was obtained from a mesenchymal stem cell SHED. Four groups were examined: neural progenitor cells cultured in neurobasal medium with (N + ) and without (N-) glutamate and glycine, and neural progenitor cells cultured in CM-SHED with (K + ) and without (K-) glutamate and glycine.ResultsThe expression of GABA A1 receptor (GABAAR1) messenger RNA (mRNA) in neural progenitor measured by real-time quantitative PCR. GABA contents were measured by enzyme-linked immunosorbent assay, whereas the apoptosis markers caspase-3 and 7-aminoactinomycin D were analysed with a Muse® cell analyzer. The viability of neural progenitor cells in the K + group (78.05 %) was higher than the control group N- (73.22 %) and lower in the N + group (68.90 %) than in the control group. The K + group showed the highest GABA content, which significantly differed from that in the other groups, whereas the lowest content was observed in the N + group. The expression level of GABAAR1 mRNA in the K + group was the highest compared to that in the other groups. CM-SHED potently protected the neural progenitors from apoptosis.ConclusionsCM-SHED may effectively prevent glutamate-induced apoptosis of neural progenitors.     

素特异性蛋白酶10在低氧性肺动脉高压中的表达及对USP10-AMPK信号通路的调控作用

目的 研究泛素特异性蛋白酶10（UPS10）在低氧性肺动脉高压（PAH）中表达的意义及对USP10-单磷酸腺苷活化蛋白激酶（AMPK）信号通路的调控作用。方法40只大鼠随机分为4组,空载组与沉默组分别经气管滴入USP10-lentivirus、NC-lentivirus,对照组与模型组滴入等量生理盐水。3 d后除对照组外均建立低氧PAH模型。以PowerLab压力记录分析系统检测各组平均肺动脉压（MPAP）、右心室收缩压（RVSP）,计算肺血管管壁相对厚度指数（RTI）、右心肥大指数（RVHI）,对比各组MPAP、RVSP、RTI、RVHI。实时荧光定量PCR技术检测USP10、AMPK、磷脂酰肌醇3激酶（PI3K）、蛋白激酶B（Akt）、内皮细胞型一氧化氮合成酶（eNOS）mRNA,比较各组USP10、AMPK、PI3K、Akt、eNOS mRNA相对表达量。蛋白质印迹法（Weston blot）检测USP10、AMPK、PI3K、Akt、eNOS蛋白及AMPK、PI3K、Akt、eNOS蛋白磷酸化表达情况,对比USP10蛋白相对表达量及p-AMPK/AMPK、p-PI3K/PI3K、p-Akt/Akt、p-eNOS/eNOS蛋白比值。结果沉默组、模型组与空载组大鼠均出现精神状态变差,活动量减少,毛发暗淡,口唇、眼眶发紫,沉默组更为严重。肺动脉血管组织HE染色观察,沉默组、模型组与空载组管壁增厚、管腔变窄,伴有平滑肌和弹力纤维层增厚,沉默组变化更为明显。与对照组比较,其余3组的MPAP、RVSP、RTI、RVHI均增加（P<0.05）,沉默组均大于模型组与空载组（P<0.05）;与对照组比较,其余3组的USP10 mRNA、蛋白相对表达量及p-AMPK/AMPK、p-PI3K/PI3K、p-Akt/Akt、p-eNOS/eNOS蛋白比值均下降（P<0.05）,沉默组均低于模型组与空载组（P<0.05）。结论USP10在低氧性PAH大鼠肺组织中表达低于正常肺组织,且其在肺组织中的表达下调刺激了PAH的发展,推测可能与抑制AMPK/PI3K/Akt/eNOS信号通路有关     

从运动神经元的TDP-43蛋白表达和ADAR2活性探讨肌萎缩侧索硬化症的发病机制

肌萎缩性侧索硬化症(ALS)是以上下两级运动神经元进行性丢失为特征的神经系统变性疾病,是运动神经元病(MND)中最常见的类型。运动神经元中的病理性TDP-43是ALS的病理特征。此外,散发性ALS运动神经元中作用于RNA的次黄嘌呤腺苷脱氢酶(ADAR2)减少、具有未经编辑Q/R位点的谷氨酸受体2(GluR2)表达增加,α-氨基-3-羟基-5-甲基-4-异恶唑丙酸受体(AMPAR)属性受影响,Ca2+通透性增加,Ca2+流入胞质增加导致神经元死亡。ALS运动神经元死亡包含病理性TDP-43和ADAR2活性下降,两种病理变化可能在细胞死亡中存在一定联系。ADAR2 mRNA是TDP-43蛋白的靶RNA,TDP-43蛋白在ADAR2的表达中起调节作用。近年来,研究者探讨ALS的基因治疗可能性:动物实验结果提示,外周静脉给予9型腺相关病毒载体(AAV9),可上调鼠运动神经元ADAR2,引发外源性ADAR2在中枢神经元表达,从而有效防治运动功能障碍。运动神经元的获救可能与TDP-43基因的正常表达有关。AAV9介导的ADAR2基因植入可能为ALS的基因治疗提供新的前景。     

脑震荡大鼠海马CA1区P-CREB的表达

目的观察磷酸化CREB（p-CREB）在脑震荡大鼠海马区的表达。方法在多聚甲醛固定的海马脑薄片上，用免疫组化法观察p-CREB在海马CA1区的表达。结果p-CREB在脑震荡大鼠海马结构CA1区的表达，1～72h增多（P〈0．05），7d后降至正常。结论p-CREB在脑震荡大鼠海马内伤后早期表达增多，P-CREB可能具有神经保护因子的作用。