Superior Institute of Biomedical Sciences, State University of Ceara, Av. Dr. Silas Munguba, 1700, Itaperi, 60714-903, Fortaleza, CE, Brazil.
Departament of Physiology and Pharmacology, Federal University of Ceara, Rua Coronel Nunes Valente, 1127, Rodolfo Teófilo, 607430-970, Fortaleza, CE, Brazil.
Biomed Pharmacother. 2018 May;101:181-187. doi: 10.1016/j.biopha.2018.02.074. Epub 2018 Feb 24.
This study aimed to chemically characterize a polysaccharide-rich extract (PRE) obtained from Genipa americana leaves and evaluate its neuroprotective effect in the brain morphology and oxidative markers using mice behavioral models.
Dry powder (5 g) of G. americana leaves were submitted to depigmentation in methanol. PRE was obtained by extraction in NaOH and precipitation with absolute ethanol and characterized by infrared spectroscopy (FTIR) and nuclear magnetic resonance (H and C NMR). Swiss mice (25-35 g) received saline (0.9% NaCl) or PRE (1-27 mg/kg) by intraperitoneal (i.p.) route, 30 min before evaluation in behavioral models (open field, elevated plus maze, sleeping time, tail suspension, forced swimming, seizures induced by pentylenetetrazole-PTZ). Animal's brain were dissected and analyzed for histological alterations and oxidative stress.
FTIR spectrum showed bands around 3417 cm and 2928 cm, relative to the vibrational stretching of OH and CH, respectively. H NMR spectrum revealed signals at δ 3.85 (methoxyl groups) and δ 2.4 (acetyl) ppm. C NMR spectrum revealed signals at δ 108.0 and δ 61.5 ppm, corresponding to C1 and C5 of α-L-arabinofuranosyl residues. PRE presented central inhibitory effect, increasing the latency for PTZ-induced seizures by 63% (9 mg/kg) and 55% (27 mg/kg), and the latency to death by 73% (9 mg/kg) and 72% (27 mg/kg). Both effects were reversed by the association with flumazenil.
PRE, containing a heteropolysaccharide, presents antioxidant and anticonvulsant effect in the model of PTZ-induced seizures via gamma-aminobutyric acid (GABA), decreasing the number of hippocampal black neurons.
本研究旨在对从 Genipa americana 叶中提取的富含多糖的提取物（PRE）进行化学表征，并使用小鼠行为模型评估其对大脑形态和氧化标志物的神经保护作用。
将 Genipa americana 叶的干粉（5g）在甲醇中进行褪色处理。通过在 NaOH 中提取并使用绝对乙醇沉淀获得 PRE，并通过红外光谱（FTIR）和核磁共振（H 和 C NMR）进行表征。瑞士小鼠（25-35g）通过腹腔（i.p.）途径接受生理盐水（0.9%NaCl）或 PRE（1-27mg/kg），在行为模型评估前 30 分钟（旷场、高架十字迷宫、睡眠时间、悬尾、强迫游泳、戊四氮-PTZ 诱导的癫痫发作）。动物的大脑被解剖并分析组织学改变和氧化应激。
FTIR 光谱显示在 3417cm 和 2928cm 左右有带，分别对应于 OH 和 CH 的振动拉伸。H NMR 光谱显示在 δ 3.85（甲氧基）和 δ 2.4（乙酰基）ppm 处有信号。C NMR 光谱显示在 δ 108.0 和 δ 61.5ppm 处有信号，分别对应于 α-L-阿拉伯呋喃糖残基的 C1 和 C5。PRE 表现出中枢抑制作用，将 PTZ 诱导的癫痫发作的潜伏期增加了 63%（9mg/kg）和 55%（27mg/kg），并将死亡潜伏期增加了 73%（9mg/kg）和 72%（27mg/kg）。两种作用都可以通过与氟马西尼的联合作用逆转。
PRE，含有一种杂多糖，通过γ-氨基丁酸（GABA）在 PTZ 诱导的癫痫发作模型中表现出抗氧化和抗惊厥作用，减少海马黑神经元的数量。
