Effects of acute administration of the hydroalcoholic extract of mate tea leaves (Ilex paraguariensis) in animal models of learning and memory

Aim of the study

Ilex paraguariensis St. Hilaire (Aquifoliaceae) is a plant widely cultivated in South America that is used to prepare a tea-like beverage with a reputation to improve cognitive function, a response that has been attributed to the constituents of the leaves, especially caffeine. Our previous study indicated that the hydroalcoholic extract of Ilex paraguariensis presents an antiparkinsonian profile in reserpine- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-treated rodents.

Materials and methods

In the present study, the effects of the hydroalcoholic extract of Ilex paraguariensis on the short- and long-term learning and memory of rats were assessed with the social recognition, Morris water maze, and step-down inhibitory avoidance tasks.

Results

A preliminary HPLC fingerprint of the plant extract confirmed the presence of caffeine (the major compound), rutin and kaemperol, and revealed the absence of detectable concentrations of caffeic acid, quercetin and ursolic acid. Acute pre-training intraperitoneal (i.p.) or oral administration of the extract of Ilex paraguariensis improved the short-term social memory in a specific manner as well as facilitated the step-down inhibitory avoidance short-term memory evaluated 1.5 h after training. Moreover, a synergistic response was observed following the co-administration of ‘non-effective’ doses of caffeine and Ilex paraguariensis in the social memory. In contrast, pre-training administration of hydroalcoholic extract of Ilex paraguariensis did not alter the step-down inhibitory avoidance long-term memory evaluated 24 h after training, while the highest dose tested (250 mg/kg, i.p.) disrupted the animals’ performance in a cued version of the Morris water maze.

Conclusion

These results partly substantiate the traditional use of mate tea for improvement of cognition indicating that acute administration of hydroalcoholic extract of Ilex paraguariensis differentially modulates short- and long-term learning and memory in rats probably through its antagonist's action on adenosine receptors.     

Water-soluble constituents from the leaves of Ilex oblonga

Four new water-soluble constituents, oblongaroside A (1), oblongar ester A (2), oblongaroside B (3), and oblongaroside C (4), were isolated along with four known compounds: 4-O-β-d-glucopyranosyl-3-hydroxybenzalcohol (5), 7-methoxyl-4-O-β-d-glucopyranosyl-3-hydroxybenzalcohol (6), 4-O-β-d-glucopyranosyl-3-hydroxybenzoic acid (7), and 3,4-dihydroxybenzoic acid (8) from the leaves of Ilex oblonga. Identification of their structures was achieved by 1D and 2D NMR experiments, including ¹H–¹H COSY, NOESY, HMQC, and HMBC methods and FAB mass spectral data.     

Genus Ilex L.: Phytochemistry, Ethnopharmacology, and Pharmacology

The genus Ilex L. has been used as remedies in traditional Chinese medicine in Aquifoliaceae and beverages for thousands of years due to abundant pharmaceutical bioactivities. There are 600 species in genus Ilex L. containing various compounds such as terpenoids, saponins, glycosides, etc. Three species, I. cornuta, I. chinensis, and I. rotunda have been admitted in Chinese Pharmacopoeia 2015 to treat dyspepsia, stomatitis, and hyperactivity cough and protect the liver and kidney. Recent studies showed that several species have been daily drunk to promote human health and prevent cardiovascular diseases in the folk. Here we reviewed the genus Ilex L. in phytochemistry, ethnopharmacology, and pharmacology.     

Triterpenoid saponins from the leaves of Ilex kudincha

Eight new triterpenoid saponins, kudinosides I-P along with three known saponins were isolated from the leaves of Ilex kudincha. The aglycone moiety of kudinosides I-K was determined as a new triterpene (kudinolic acid), a fore-genin for the lactonic triterpene. The structures of all saponins were established on the basis of spectroscopic and chemical evidence. The biogenesis of the triterpene with lactonic moiety was briefly discussed.     

Two new triterpenoid saponins from Ilex cornuta

Two new triterpenoid saponins (1 and 2) were isolated from the stems of Ilex cornuta, along with two known triterpenoids (3 and 4). The structures of compounds 1 and 2 were determined as ursane-12,19-diene-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (1), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-O-β-d-glucopyranosyl ester (2), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds 1–4 were tested against H₂O₂-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.     

岗梅茎中的酚类成分研究

综合运用多种色谱技术从岗梅茎的水提物中分离得到了18个酚类成分,经波谱学方法鉴定其结构,包括2个木脂素类(1,2),5个苯丙素类(3~7),6个绿原酸类(8~13),5个苯甲酸类似物(14~18),其中3~7,9,11,13,14,17,18为首次从冬青属中分离得到,2,8,10,15,16为首次从岗梅中分离得到。抗炎活性筛选结果显示,8,9,11,13,15对RAW264.7细胞中的NO生成显示有一定的抑制作用,其IC50为51.1~85.8μmol·L-1。该研究为进一步阐明岗梅茎的抗炎药效物质及药材的质量评价研究提供了参考。     

枸骨叶中的黄酮类成分(英文)

目的:研究枸骨Ilex cornuta Lindl.ex Paxt.叶的黄酮类成分。方法:利用硅胶柱色谱和半制备高效液相色谱对枸骨的叶进行分离纯化, 利用光谱学手段结合理化性质鉴定其结构。结果:分离鉴定了9个黄酮类化合物, 分别为:山柰酚-3-O-β-D-吡喃葡萄糖(1→2)-α-L-吡喃阿拉伯糖苷(1),槲皮素-3-O-β-D-吡喃葡萄糖(1→2)-α-L-吡喃阿拉伯糖苷(2),异鼠李素-3-O-β-D-吡喃葡萄糖苷(3),金丝桃苷(4),3’-甲氧基大豆苷(5),异鼠李素(6),芒柄花素(7),山柰酚(8),槲皮素(9).结论:化合物1为新的黄酮类成分。     

RP-HPLC-DAD法同时测定毛冬青根中4种三萜皂苷和2种木脂素的含量

建立了反相高效液相色谱-二极管阵列检测法同时测定毛冬青根中的6种活性成分（tortoside A,（＋）-丁香脂素,毛冬青皂苷B3,毛冬青皂苷A1,毛冬青皂苷B1,毛冬青素A）的含量。RP-HPLC分离用反相C18分析柱,流动相以乙腈-0.1%磷酸水体系梯度洗脱。流速1.0 mL/min,检测波长为210 nm。6个指标成分达到基线分离,标准曲线具有良好的线性（r2〉0.9996）,精密度、稳定性和重复性符合分析方法学要求。加样回收率范围为99.00%–104.52%。最后对15个批次的毛冬青药材含量测定结果进行了聚类分析。结果表明该方法不仅可以对毛冬青药材进行质量控制,而且也为毛冬青药材的道地性分析提供了科学依据。     

A new para-quinone-type flavan from the leaves of Ilex centrochinensis and its anti-inflammatory activities

A new para-quinone-type flavan, (2S)-7-methoxy-3′,4′-dihydroxy-5,8-quinoflavan (1), together with three known compounds, were isolated from the leaves of Ilex centrochinensis. Their structures were elucidated by detailed spectroscopic analyses for new structure and in comparison with published data for known compounds. Moreover, the new compound was evaluated its cytotoxic and anti-inflammatory activities in vitro on LPS induced RAW 264.7 cells and the results showed that 1 has promising anti-inflammatory activities.     

Triterpenoid Saponins from the Leaves of Ilex Kudincha

Abstract

Eight new triterpenoid saponins, kudinosides I-P along with three known saponins were isolated from the leaves of Ilex kudincha. The aglycone moiety of kudinosides I-K was determined as a new triterpene (kudinolic acid), a fore-genin for the lactonic triterpene. The structures of all saponins were established on the basis of spectroscopic and chemical evidence. The biogenesis of the triterpene with lactonic moiety was briefly discussed.