头花蓼对α-葡萄糖苷酶的抑制活性研究

目的 :研究头花蓼不同溶剂提取物对 α -葡萄糖苷酶的抑制活性。 方法 :采用索氏提取法对头花蓼进行不同溶剂提取,以体外法测定各提取物对 α- 葡萄糖苷酶的抑制作用。 结果: 头花蓼各提取物均具有较好的 α -葡萄糖苷酶抑制活性。其中头花蓼的甲醇提取物抑制活性最高(IC₅₀ 1.68 μg·mL^-1),乙酸乙酯提取物(IC₅₀ 7.27 μg·mL^-1)和石油醚提取物(IC₅₀ 116.81 μg·mL^-1)的活性次之。3个提取物活性均远大于阳性对照acarbose(IC₅₀ 1 081.27 μg·mL^-1)。且各提取物对 α- 葡萄糖苷酶的抑制作用均具有剂量依赖性。 结论: 头花蓼甲醇提取物对 α- 葡萄糖苷酶活性的抑制效果非常显著,具有很好的开发价值。     

青龙衣毒性作用及体外抗肿瘤作用的实验研究

目的 :青龙衣提取物及其分离成分的毒性及体外抗肿瘤作用。方法 :采用常规小鼠急性毒性试验方法 ,MTT [3-(4 ,5-dimethylthiazol -2 yl)-2 ,5-diphenylterazolium bromide ,MTT]法和SRB(sulforhodamin B)法对青龙衣提取物及其分离成分的抗肿瘤作用进行了初步筛选。结果 :除小鼠腹腔注射青龙衣氯仿萃取物LD₅₀ 为575.38mg·kg^-1和青龙衣醋酸乙酯萃取物为1303.59mg·kg^{-1,青龙衣总提取物和青龙衣石油醚萃取物、正丁醇萃取物和水萃取物小鼠口服及腹腔注射LD50 均大于 5g·kg-1。醋酸乙酯粗提部分对人白血病细胞株HL60在100 μg·mL-1时 ,细胞抑制率 <50 % ,在 100μg·mL-1剂量下 ,青龙衣的氯仿粗提部分和醋酸乙酯粗提部分对白血病细胞株HL6 0、人胃癌细胞株BGC823及人宫颈癌细胞株Hela细胞的抑制率均>50% ,其IC₅₀ (生长抑制 ) <100μg·mL-1。结论 :青龙衣氯仿提取物和醋酸乙酯提取物具有一定的抗肿瘤作用。}     

新疆阿魏内生真菌链格孢属菌提取物体外抑制肿瘤增殖活性筛选

目的 评价新疆阿魏内生真菌提取物体外抗肿瘤细胞增殖活性,并筛选具有抗肿瘤细胞增殖活性的菌株,为进一步研究其抗肿瘤作用提供依据。方法 采用四甲基偶氮唑盐（MTT）法测定117株新疆阿魏内生真菌菌液提取物和菌丝体提取物对人宫颈癌HeLa细胞和胃癌AGS细胞增殖的影响。结果 有43株链格孢属菌株的49份提取物在质量浓度为100 μg·mL^–1时,对肿瘤细胞抑制率达50%以上;其中15份对HeLa细胞、AGS细胞的增殖均具有显著抑制作用,且1938/TL168菌株提取物对HeLa细胞增殖的半数抑制浓度（IC₅₀）低至（25.95±3.39）μg·mL^–1。结论 阿魏内生真菌提取物可有效抑制肿瘤细胞增殖,具备抗肿瘤药物研发潜质。     

茶叶、槐米、金荞麦、红花醇提物的抗氧化活性的比较研究

目的:比较茶叶、槐米、金荞麦、红花的70%乙醇提取物的抗氧化活性。方法:低温条件下制备大鼠肝微粒体,建立Fe²⁺-ADP-NADPH体外氧化体系,通过计算半数抑制浓度评价上述4种中药的抗氧化活性。结果:茶叶、槐米、金荞麦、红花的IC₅₀分别为0.030,0.041,0.324,0.598mg·mL^-1。结论:4种提取物均有抗脂质过氧化活性,且活性由大到小依次为茶叶、槐米、金荞麦、红花。     

新疆阿魏树脂不同分离部位对结肠癌细胞HCT116的抑制作用

目的: 分析新疆阿魏树脂不同分离部位对结肠癌细胞HCT116抑制作用的活性,并确定其有效活性部位。 方法: 通过磺酰罗丹明B比色法（SRB）与流式细胞术以细胞密度1×10⁵个mL,药物质量浓度250,125,62.5,31.25,15.6 mg·L^-1（流式细胞术药物浓度为62.5 mg·L^-1）,检测新疆阿魏树脂不同分离部位（石油醚部位、乙酸乙酯部位,甲醇部位）对结肠癌细胞 HCT116药物作用24 h后的增殖抑制与凋亡作用,以IC₅₀和总凋亡率作为指标衡量其各分离部位抑制肿瘤的活性效能。 结果: 石油醚部位:对结肠癌细胞HCT116增殖抑制IC₅₀ 68.7 mg·L^-1,总凋亡率为（43.4±1.1）%;乙酸乙酯部位:IC₅₀43.7 mg·L^-1, 总凋亡率为（56.2±0.9）%;甲醇部位:IC₅₀59.6 mg·L^-1,总凋亡率为（46.7±3.1）%。 结论: 新疆阿魏树脂乙醇提取物的乙酸乙酯萃取部位对结肠癌细胞HCT116细胞毒性作用较强并能促进其大量凋亡,初步确定为新疆阿魏树脂抗肿瘤活性部位。     

半边旗中二萜类化合物的植化及抗肿瘤活性初步研究

 目的:对半边旗中二萜类有效成分及抗肿瘤活性作进一步研究?方法:半边旗乙醇提取物上活性炭柱,乙醇-氯仿(10∶1)洗,减压浓缩后上硅胶柱,甲醇-氯仿(90∶2)洗脱,得纯化合物,经二维核磁共振(NMR)确定了化合物的空间结构?以噻唑蓝(MTT)法测定肿瘤细胞存活率,?IC50按改良Karber公式计算?结果:共分得5个化合物B,4F,5F,6F及A,其中A是新化合物,6F是首次从该植物中分离得到?5F,A,6F明显抑制人白血病粒细胞HL-60,人低分化胃腺癌上皮细胞MGC-803、人低分化鼻咽癌上皮细胞CNE-2Z和人肝癌上皮细胞BEL-7402的增殖,活性依次增强?6F对HL-60细胞的活性最强[IC₅₀为(0.09±0.01)μmol·L^-1],阳性对照5Fu的IC₅₀为:(52.5±2.8)μmol·L-1?结论:从半边旗分离得到的一类二萜化合物具有显著抑制多种癌细胞增殖的活性,其中6F活性最强?     

桂枝茯苓胶囊提取物的体外抗肿瘤活性及机制

 目的 比较桂枝茯苓胶囊不同溶剂提取物的体外抗肿瘤活性,并探讨其可能的机制。方法 采用四甲基偶氮唑蓝法观察桂枝茯苓胶囊不同溶剂提取物对HeLa和C33A 2种人宫颈癌细胞株增殖的影响,以酶联免疫吸附法测定蛋白酪氨酸激酶(protein tyrosine kinases, PTKs)活性,用二苯代苦味肼基 (1,1-diphenyl-2-picrylhydrazyl, DPPH) 清除率方法测定体外抗氧化活性。结果 桂枝茯苓胶囊的多种溶剂提取物具有良好的人宫颈癌细胞生长抑制活性。对HeLa细胞的抑制强度最大者为正丁醇部分-30%乙醇洗脱物 (提取物9),IC₅₀为（7.09±1.25）μg·mL^-1,对C33A细胞的抑制强度最大者为乙酸乙酯部分-丙酮洗脱物 (提取物5),IC₅₀为（5.14±0.70）μg·mL^-1。结论 桂枝茯苓胶囊提取物在体外显示不同的抗肿瘤活性,抑制蛋白酪氨酸激酶活性以及抗氧化作用可能是其提取物抗肿瘤作用的机制之一。     

UPLC-QTOF/MS分析芫花诱导人肝细胞L02损伤的毒性物质基础

目的: 研究芫花提取物诱导人肝细胞L02损伤的毒性物质基础。 方法: 选取人肝细胞L02作为体外实验模型,运用MTT法测定芫花提取物对细胞增殖的影响,并且采用超高效液相色谱串联四级杆飞行时间质谱(UPLC-QTOF/MS)对芫花提取物及与L02细胞亲和后胞内化学成分进行定性分析。 结果: 芫花提取物对L02细胞的生长抑制呈明显的剂量依赖关系,48 h的IC₅₀为(48.34±4.66)mg·L^-1。通过UPLC-QTOF/MS鉴定的黄酮类成分主要有:芹菜素、3'-羟基芫花素、芫花素、5,4'-二羟基-7,3'-二甲氧基黄酮;二萜原酸酯类成分主要有:芫花酯戊、genkwanine L、芫花酯丙、芫花烯、芫花酯丁、芫花酯庚、芫花酯乙、芫花酯己、芫花酯甲。在芫花提取物亲和的L02细胞中鉴定出3'-羟基芫花素、芫花素、5,4'-二羟基-7,3'-二甲氧基黄酮、芫花酯戊、芫花烯、芫花酯丁、芫花酯乙、芫花酯甲。其中二萜原酸酯类成分芫花酯甲作用L02细胞48 h的IC₅₀为(29.57±2.01) mg·L^-1,黄酮类成分芫花素(0.1～100 mg·L^-1)未发现对L02有显著的细胞毒作用。 结论: 芫花提取物对人肝细胞L02具有细胞毒作用,其中二萜原酸酯类成分与细胞有明显的亲和作用,并具显著的细胞毒作用,是芫花提取物中主要的活性物质。     

5种中药乙醇提取物的体外抗氧化活性研究

目的: 研究马尾松等5种中药的乙醇提取物的体外抗氧化活性。 方法: 采用乙醇超声提取法获得各中药提取物,并以抗坏血酸(VitC)为阳性对照来考察其对超氧阴离子(O₂^-·)、羟自由基(·OH)、1,1-二苯基-2-三硝基苯肼自由基(DPPH·)的清除效果。 结果: 甘草、丹参、马尾松、当归、罗汉松对O₂^-·的抑制率分别为(浓度相当于原药材100 g·L^-1):15.86%,11.68%,11.31%,7.88%,5.94%;在清除DPPH·的实验中各中药的IC₅₀(g·L^-1)分别为:丹参1.6,马尾松1.87,罗汉松3.11,甘草13.91,当归22.32;而在清除·OH的实验中各中药的IC₅₀(g·L^-1)则为:丹参1.6,罗汉松2.02,马尾松2.1,甘草2.77,当归4.03;而三大体系阳性对照的IC₅₀分别为0.047,0.93,0.21 g·L^-1。 结论: 5种中药乙醇超声提取物均具有一定的抗氧化活性,其中丹参、马尾松效果较好;但与阳性对照Vit C相比仍有一定差距。     

藏药松生等醇提物不同极性提取部分体外抗氧化活性研究

目的: 通过体外还原力和抗氧化评价方法研究藏药松生等提取物的抗氧化活性。 方法: 将松生等用70% 乙醇浸泡、提取、浓缩所得浸膏依次用石油醚, 二氯甲烷,乙酸乙酯, 正丁醇、乙醇进行萃取,各组分都配制成适当稀释倍数的溶液, 通过普鲁士蓝法、Fenton法和,1,1-二苯基-2-三硝基苯肼(DPPH)法分别测定各组分的还原力,·OH自由基的清除能力以及抗氧化的活性,并计算各组分的IC₅₀。 结果: 3种抗氧化实验表明乙酸乙酯、正丁醇、乙醇部分都具有明显抗氧化的作用。其中用DPPH法测得的IC₅₀分别是乙酸乙酯0.060 5 g·L^-1,正丁醇0.076 3 g·L^-1,乙醇0.083 3 g·L^-1。 结论: 提取物清除率与样品浓度存在明显的量效关系,浓度大于1.0 g·L^-1时其还原能力几乎接近于维生素(VC),清除能力接近甚至超过60%。其中在大极性溶液层还原力和抗氧化的能力最强。     

侧柏叶不同提取部位抑制胰脂肪酶及抗氧化活性筛选

目的:考察侧柏叶不同提取部位体外抑制胰脂肪酶活性和抗氧化活性。方法:对侧柏叶的醇提液、石油醚部位、乙酸乙酯部位、正丁醇部位、水部位采用体外抑制胰脂肪酶活性研究,并通过其清除1,1二苯基苦基苯肼(DPPH)自由基和Fe3+还原能力(FRAP)测定侧柏叶提取物的体外抗氧化作用。结果:侧柏叶提取物均有不同程度抑制胰脂肪酶活性,以乙酸乙酯部位效果最佳(IC50为26.09 mg·L-1),其次正丁醇部位(IC50为39.02 mg·L-1)和醇提物(IC50为98.20 mg·L-1),石油醚部位(IC50为188.27 mg·L-1)和水部位(IC50为325.28 mg·L-1)最弱。抗氧化活性依次为醇提液(DPPH IC50为7.59 mg·L-1,FRAP 4.40 mmol·g-1)乙酸乙酯部位(DPPH IC50为8.28 mg·L-1,FRAP 3.82 mmol·g-1)正丁醇部位(DPPH IC50为24.21mg·L-1,FRAP 1.77 mmol·g-1)水部位(DPPH IC50为27.53 mg·L-1,FRAP 1.38 mmol·g-1)石油醚部位。结论:初步确定侧柏叶抑制胰脂肪酶活性有效成分主要在乙酸乙酯与正丁醇部位,抗氧化及其相关成分主要在乙酸乙酯部位。     

美洲大蠊不同提取物及不同提取方法对肿瘤细胞的细胞毒性作用

目的:研究美洲大蠊不同提取物及不同提取方法对肿瘤细胞的细胞毒性,为美洲大蠊的抗肿瘤细胞研究提供实验依据。方法:以人肝癌SMMC-7721细胞株,红白血病细胞株K562,人结肠癌细胞株HCT116 3种肿瘤细胞为研究对象,采用细胞计数试剂盒-8(CCK-8)法,比较不同的提取物(乙醇提取液、石油醚部位、乙酸乙酯部位、正丁醇部位)和不同的提取方法(渗漉法、超声法、回流法)对3种肿瘤细胞的体外抗肿瘤活性。结果:美洲大蠊乙醇提取液和乙酸乙酯部位对上述肿瘤细胞增殖均有不同程度的抑制作用,其中以乙醇提取液的活性最强;3种提取方法提取的美洲大蠊均表现出不同程度的体外抗肿瘤活性,其中以渗漉法提取的美洲大蠊对3种肿瘤细胞的抑制作用最强,所计算出的半数抑制浓度(IC50)均最小。结论:美洲大蠊乙醇提取液的体外抗肿瘤活性最强,乙酸乙酯部位次之,美洲大蠊宜选择渗漉法提取。     

不同天数银杏叶发酵液提取物的体外抗氧化活性比较

目的： 考察银杏叶培养基经过冠突散囊菌发酵不同时间后乙酸乙酯提取物的体外抗氧化活性。 方法： 将冠突散囊菌接种于银杏叶培养基中分别发酵4,7,11,14 d后,真空抽滤得到滤液,利用溶剂分级萃取得到提取液,以未发酵银杏叶乙 酸乙酯提取液作为对照。结合酶标仪,通过清除DPPH（1,1-二苯基-2-三硝基苯肼）自由基、ABTS 自由基,以及铁还原能力,比较不同发酵天数乙酸乙酯提取物的抗氧化能力。 结果： 测定了不同天数银杏叶发酵液乙酸乙酯提取物的抗氧化活性,发现11 d发酵液提取物抗氧化活性最强,DPPH半数抑制浓度（IC₅₀）105.60 mg·L^-1,ABTS IC₅₀ 102.09 mg·L^-1更接近维生素C（VC）的IC₅₀值,同时,11 d组铁还原实验的吸光度在不同浓度梯度下均为最大值。 结论： 初步确定银杏叶培养基发酵11 d后,发酵液中的抗氧化活性成分积累量最大。     

Screening of medicinal plants from Iranian traditional medicine for acetylcholinesterase inhibition

To find new herbal compounds with an acetylcholinesterase (AChE) inhibitory effect, this study focused on herbal drugs and resins which have been used in Iranian traditional medicine for the treatment of cognitive disorders. Forty drugs were selected from authoritative written documents of Iranian traditional medicine. Each drug was extracted by accelerated solvent extraction using dichloromethane followed by methanol. The 80 extracts were screened for AChE inhibitory activity by a TLC bioautography method. The inhibiting effect of the 32 most active extracts was measured by a microplate colorimetric assay. Due to the best activity, the seeds of Peganum harmala L. were investigated in detail. From the TLC bioautography assay the alkaloids harmaline and harmine were identified as active compounds. This result was confirmed by means of HPLC‐DAD. The IC₅₀ values were 41.2 μg/mL for the methanol extract, 95.5 μg/mL for the dichloromethane extract, 8.4 μg/mL for harmaline and 10.9 μg/mL for harmine. The concentrations of active compounds in the extracts were determined by a fast and precise HPLC method. As the amounts of harmaline and harmine in the extracts were correlated with the IC₅₀ values of the extracts, it can be concluded that these two alkaloids are responsible for the AChE inhibitory activity of P. harmala. Copyright © 2011 John Wiley & Sons, Ltd.     

卷柏中雌激素类成分的提取

目的:对不同提取方法所得的卷柏提取物进行雌激素活性筛选,探索卷柏发挥雌激素作用的活性部位。方法:采用小鼠子宫增重试验,将卷柏分别以70%乙醇回流所得总部位经聚酰胺柱分离;95%乙醇回流药渣经水提取;药渣水提物去除多糖等所得的卷柏各组分进行雌激素活性筛选。运用HPLC指纹图谱技术对卷柏95%醇提物、药渣水提物进行分析。结果:70%乙醇回流所得的卷柏总部位、药渣水提物高剂量、药渣水提物去多糖组与空白组比较,均能显著性增加小鼠子宫系数(P<0.01),卷柏其余各组与空白组相比无明显作用;HPLC指纹图谱显示卷柏95%醇提物中穗花杉双黄酮为其主要成分,而药渣水提物中基本不含穗花杉双黄酮。结论:95%乙醇回流药渣水提法与聚酰胺柱分离法相比,前者更适合于卷柏雌激素活性物质的提取分离;水溶性除多糖物质为卷柏中发挥雌激素样作用的有效部位;HPLC指纹图谱结果提示,穗花杉双黄酮不是卷柏发挥雌激素作用的成分。     

Screening of plants used in Danish folk medicine to treat depression and anxiety for affinity to the serotonin transporter and inhibition of MAO-A

Ethnopharmacological relevance

A number of plant species are used in Danish folk medicine for treatment of depression and anxiety.

Materials and methods

Aqueous and ethanolic extracts of 17 plant species were tested for affinity to the serotonin transporter and for inhibition of MAO-A—both targets for antidepressive treatment.

Results

An ethanolic extract of aerial parts of Borago officinalis had affinity to the serotonin transporter. Ten extracts, from eight plants, had IC₅₀ values below 25 μg/ml extract in the MAO-A assay. The most active extracts in the MAO-A assay were the ethanol extract of seeds of Trigonella foenum-graecum (IC₅₀ 4 μg/ml); ethanol extract of leaves of Apium graveolens (IC₅₀ 5 μg/ml) and the water extract of aerial parts of Calluna vulgaris (IC₅₀ 8 μg/ml).

Conclusions

Besides Borago officinalis, which toxicity profile excludes it from further development as an herbal drug, none of the plants had potential as serotonin reuptake inhibitors. Several plants had MAO-A inhibitory activity.     

Comparative biological study of roots,stems, leaves,and seeds of Angelica shikokiana Makino

Ethnopharmacological relevance

Angelica shikokiana has been used as a health food for its anticancer, anti-inflammatory, antibacterial, antiallergic, and blood vessel dilating effects in Japan. It can also be used to prevent and treat hepatitis, diabetes, hyperlipidemia, and arteriosclerosis.

Aim of the study

The present study was designed to compare the biological activities such as melanin synthesis inhibitory, anti-allergy, anti-lipase, anti-bacterial, anti-oxidant, and neuroprotective activities of different parts of the plant that may justify the use of this plant in folk medicine.

Material and methods

The roots, stems, leaves and, seeds of Angelica shikokiana were separately extracted with water and ethanol. Each extract was examined for melanin synthesis inhibitory and anti-allergy activity on B16-melanoma and RBL-2H3 cells using IgE and A23187 as a stimulant for β-hexosaminidase release, respectively. We also evaluated the inhibition of two enzymes, lipase and acetylcholine esterase, and of the bacterial growth of two species, Escherichia coli and Staphylococcus aureaus. The anti-oxidant activity was determined using oxygen radical anti-oxidant capacity, ORAC assay and its relation to the phenolic content was estimated using the Folin–Ciocalteu method. Besides, the protective effect of the extracts against H₂O₂-induced oxidative stress in mouse neuroblastoma, Neuro-2A cells was investigated.

Results

The most active extract exhibiting melanin synthesis inhibition (63%) and at the same time with low cytotoxicity (15%) was the ethanol extract of roots at 20 µg/ml, followed by the ethanol extract of stems (57% inhibition, 5% cytotoxicity). On the other hand, the highest inhibitions of β-hexosaminidase release were recorded for the ethanol extract of leaves with IC₅₀ value of 6.89 µg/ml followed by the water extract of the seeds and leaves with IC₅₀ value of 78.32 and 88.44 µg/ml, respectively. For anti-lipase assay, ethanol extracts of the stems and roots showed the strongest inhibition with IC₅₀ values of 204.06 and 216.24 µg/ml, respectively. None of the examined extracts showed any activity against Escherichia coli. while the ethanol extract of the roots and stems showed moderate inhibition for Staphylococcus aureus with minimum inhibitory concentration of 400 µg/ml. Ethanol extract of the roots showed only 30% inhibition of acetylcholine esterase enzyme. The results of anti-oxidant, phenolic content and protective effect against H₂O₂-induced cytotoxicity assays showed highly correlated data. Ethanol extract of the stems (ORAC value of 1.08 µmol Trolox/ mg and phenolic content 44.25 μg GAE/mg) increased the cell viability of H₂O₂-treated Neuro-2A cells by 28%.     

In vitro antitrypanosomal and antiplasmodial activities of crude extracts and essential oils of Ocimum gratissimum Linn from Benin and influence of vegetative stage

Ethnopharmacological relevance

Different parts of Ocimum gratissimum Linn are largely used in folk medicine for the treatment of many diseases, some of which related to parasitical infections as fevers and headaches. In order to validate their use and to clarify the plant part which possesses the best antiparasitic properties, we decided to evaluate the in vitro antiplasmodial and antitrypanosomal activities of essential oils and crude extracts from leaves, stems and seeds of Ocimum gratissimum as well as their cytotoxicity.

Materials and methods

The essential oils and ethanol crude extracts of leaves and stems of Ocimum gratissimum from Benin, were obtained in pre and full flowering stages. Seeds obtained only in full flowering stage, were also extracted. The oils were isolated by hydrodistillation and analyzed by GC/MS and GC/FID. Extracts and essential oils were tested in vitro against Trypanosoma brucei brucei and Plasmodium falciparum. Cytotoxicity was evaluated in vitro against Chinese Hamster Ovary (CHO) cells and the human non cancer fibroblast cell line (WI38) through MTT assay to evaluate the selectivity and toxicity was assessed against Artemia salina Leach.

Results

The essential oils and non-volatile crude extracts of Ocimum gratissimum were more active on Trypanosoma brucei brucei than on Plasmodium falciparum (3D7). This activity varies according to the vegetative stage (pre and full flowering) and the plant part (seeds, stems and leaves) extracted. The best growth inhibition of Trypanosoma brucei brucei was observed with ethanol crude extracts of leaves (IC₅₀=1.66±0.48 μg/mL) and seeds (IC₅₀=1.29±0.42 μg/mL) in full flowering stage with good selectivity (SI>10). The chemical composition of the essential oil from aerial parts (47 compounds), characterized by the presence as main constituents of p-cymene, thymol, γ-terpinene, β-myrcene and α-thujene, depends on the vegetative stage. The oil contained some minor compounds such as myrcene (IC₅₀=2.24±0.27 μg/mL), citronellal (IC₅₀=2.76±1.55 μg/mL), limonene (IC₅₀=4.24±2.27 μg/mL), with good antitrypanosomal activities. These oils and crude extracts were not toxic against Artemia salina Leach and had a low cytotoxicity except leaves and seeds ethanol extracts obtained in full flowering which showed toxicity against CHO and WI38 cells.

Conclusions

Our study shows that ethanol crude extracts of leaves and seeds of Ocimum gratissimum in full flowering stage can be a good source of antitrypanosomal agents. This is the first report about the relation between the plant part extracted, the vegetative stage of the plant, the antitrypanosomal and antiplasmodial activities and the cytotoxicity of essential oils and non-volatile extracts of Ocimum gratissimum from Benin.     

In vitro anti-breast cancer activity of ethanolic extract of Wrightia tomentosa: Role of pro-apoptotic effects of oleanolic acid and urosolic acid

Ethnopharmacological relevance

Wrightia tomentosa Roem. & Schult. (Apocynaceae) is known in the traditional medicine for anti-cancer activity along with other broad indications like snake and scorpion bites, renal complications, menstrual disorders etc. However, the anti-cancer activity of this plant or its constituents has never been studied systematically in any cancer types so far.

Aim of the study

To evaluate the anti-cancer activities of the ethanolic extract of W. tomentosa and identified constituent active molecule(s) against breast cancer.

Material and methods

Powdered leaves of W. tomentosa were extracted with ethanol. The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa were tested for its anti-proliferative and pro-apoptotic effects in breast cancer cells MCF-7 and MDA-MB-231.

Results

The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa inhibited the proliferation of human breast cancer cell lines, MCF-7 and MDA-MB-231. The fraction F-4 obtained from hexane fraction inhibited proliferation of MCF-7 and MDA-MB-231 cells in concentration and time dependent manner with IC₅₀ of 50 μg/ml and 30 μg/ml for 24 h, 28 μg/ml and 22 μg/ml for 48 h and 25 μg/ml and 20 μg/ml for 72 h respectively. The fraction F-4 induced G1 cell cycle arrest, reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential and subsequent apoptosis. Apoptosis is indicated in terms of increased Bax/Bcl-2 ratio, enhanced Annexin-V positivity, caspase 8 activation and DNA fragmentation. The active molecule isolated from fraction F-4, oleanolic acid and urosolic acid inhibited cell proliferation of MCF-7 and MDA-MB-231 cells at IC₅₀ value of 7.5 μM and 7.0 μM respectively, whereas there is devoid of significant cell inhibiting activity in non-cancer originated cells, HEK-293. In both MCF-7 and MDA-MB-231, oleanolic acid and urosolic acid induced cell cycle arrest and apoptosis as indicated by significant increase in Annexin-V positive apoptotic cell counts.

Conclusion

Our results suggest that W. tomentosa extracts has significant anti-cancer activity against breast cancer cells due to induction of apoptosis pathway. Olenolic and urosolic acid are important constituent molecules in the extract responsible for anti-cancer activity of W. tomentosa.