Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain.
J Pineal Res. 2010 Sep;49(2):141-8. doi: 10.1111/j.1600-079X.2010.00778.x. Epub 2010 Jun 1.
Melatonin is a potent free radical scavenger, antioxidant and neuroprotective drug. On the other hand, galantamine is a cholinergic drug with antioxidant and neuroprotective properties linked to inhibition of acetylcholinesterase and allosteric modulation of nicotinic receptors. This investigation evaluated a possible synergistic neuroprotective effect of subeffective concentrations of combined galantamine and melatonin. Human neuroblastoma SH-SY5Y cells were subjected to a mitochondrial oxidative stress, by blockade of mitochondrial complexes I and V with rotenone and oligomycin-A (R/O); cells were treated for 24 hr with R/O. This caused 40% of the cell to die as measured by lactate dehydrogenase (LDH) release. Cell incubation with increasing concentrations of galantamine (10-300 nm) or melatonin (0.3-10 nm) for 24 hr, followed by a 24-hr period with R/O, caused a concentration-dependent protection; maximum protection was achieved with 300 nm galantamine (56% protection) and 10 nm melatonin (50% protection). Combination of subeffective concentrations of melatonin (0.3 nm) and galantamine (30 nm) caused a synergistic and significant protection that was similar to the maximum protection afforded by effective concentrations of melatonin or galantamine alone. This protective effect was completely reversed when nicotinic and melatonin receptors were blocked respectively by mecamylamine and luzindole. The neuroprotective effect was prevented by chelerythrine, LY294002, and Sn (IV) protoporphyrin IX dichloride (SnPP), indicating the participation of the PKC/PI3K/Akt activation and induction of the antioxidant enzyme heme oxygenase-1. The synthesis of novel multitarget compounds having in a single molecule the combined neuroprotective properties of galantamine and melatonin could be a new strategy for potential therapeutic agents in neurodegenerative diseases.
褪黑素是一种有效的自由基清除剂、抗氧化剂和神经保护药物。另一方面，加兰他敏是一种具有抗氧化和神经保护特性的胆碱能药物，其作用机制与抑制乙酰胆碱酯酶和变构调节烟碱型受体有关。本研究评估了联合使用低浓度褪黑素和加兰他敏的协同神经保护作用。将人神经母细胞瘤 SH-SY5Y 细胞用鱼藤酮和寡霉素 A（R/O）阻断线粒体复合物 I 和 V 进行线粒体氧化应激处理；细胞用 R/O 处理 24 小时。通过乳酸脱氢酶（LDH）释放测定，有 40%的细胞死亡。细胞孵育 24 小时，用不同浓度的加兰他敏（10-300nm）或褪黑素（0.3-10nm）处理，然后用 R/O 处理 24 小时，导致浓度依赖性保护；用 300nm 加兰他敏（56%保护）和 10nm 褪黑素（50%保护）获得最大保护。联合使用低浓度褪黑素（0.3nm）和加兰他敏（30nm）可产生协同且显著的保护作用，与褪黑素或加兰他敏单独有效浓度所提供的最大保护作用相似。当分别用美金刚和 luzindole 阻断烟碱和褪黑素受体时，这种保护作用被完全逆转。神经保护作用被 chelerythrine、LY294002 和 Sn（IV）原卟啉 IX 二氯化物（SnPP）阻止，表明 PKC/PI3K/Akt 激活和诱导抗氧化酶血红素加氧酶-1 的参与。在单个分子中结合加兰他敏和褪黑素的联合神经保护特性的新型多靶化合物的合成可能是神经退行性疾病潜在治疗剂的新策略。
