Kinuthia Dennis Gacigi, Muriithi Anne W, Mwangi Peter Waweru
Department of Medical Physiology, School of Medicine, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya.
J Ethnopharmacol. 2016 Dec 4;193:416-422. doi: 10.1016/j.jep.2016.09.041. Epub 2016 Sep 21.
Diarrhea remains one of the main killers of children aged below five years. Traditional antidiarrheal remedies form a potentially viable source of novel low cost efficacious treatments in low resource settings. There is therefore a pressing need to scientifically evaluate these remedies.
This study aimed to investigate the in vivo and in vitro antidiarrheal activity of freeze dried Bidens biternata, a herb used in traditional Ayurvedic medicine in the management of diarrhea.
In the castor oil test, twenty (20) adult Sprague-Dawley rats were randomized to a negative control (normal saline, n=5), a positive control (5mg/kg loperamide, n=5), and two test groups. The low dose test group received 200mg/kg Bidens biternata extract (n=5) while the high dose test group received 400mg/kg B. biternata extract (n=5). Castor oil (4ml/kg) was then administered to the animals one hour after administration of the respective treatments after which the total mass of fecal output excreted after four (4) hours was determined. In the charcoal meal test fifteen (15) Sprague Dawley rats were randomized to a control group (normal saline 5ml/kg orally, n=5), a positive control group (atropine sulfate 0.1mg/kg i.p., n=5) and a test group (400mg/kg B. biternata extract, n=5). Charcoal meal was then administered via oral gavage to each rat thirty (30) minutes after the administration of the various treatments. The distance covered by the charcoal meal from the pylorus was then determined after sacrifice of the animals thirty minutes after the meal. In the enteropooling test twenty (20) Sprague-Dawley rats were randomized to a control group (5% v/v ethanol in normal saline, n=5), a positive control group (5mg/kg loperamide, n=5) and a test group (400mg/kg B. biternata extract, n=5). For each group prostaglandin E2 (PGE2) (100μg/kg) was administered immediately after the treatments. The animals were then sacrificed half an hour later and the volume of the small intestine contents determined. The effects of different concentrations of B. biternata extract (0.5. 1.0, 2.0, 3.0 and 5.0mg/ml) on jejunal contraction were investigated and a dose-response curve constructed using the experimental data after which The ED50 dose was determined. The effect of tamsulosin (α1 adrenergic blocker), yohimbine (α2 adrenergic blocker), propranolol (β adrenergic blocker) and naloxone (μ opioid blocker) on the contractile activity of the extract were also investigated. The experimental data were expressed as mean±standard error of mean (SEM) and then analyzed using one-way ANOVA followed by Tukey's post hoc test in cases of significance (set at p<0.05).
The freeze dried extracts of B. biternata had significant antidiarrheal effects in the castor oil induced diarrhea model (p<0.01) with the highest activity being observed at the 400mg/kg dosage level (1.66±0.81g vs. 4.54±0.51g control, p=0.01). B. biternata extract had significant effects on intestinal motility in the charcoal meal test compared to the control group (43.61±4.42% vs. 60.54±3.33%: p<0.05). B. biternata extract had a significant effect on PGE2 induced enteropooling (3.06±0.07ml vs. 4.74±0.10ml; p<0.001). The freeze dried extracts of B. biternata had a significant negative effect on the contractility of the isolated rabbit jejunum (p<0.001). The effects of the extract were significantly attenuated by tamsulosin (53.94±4.20% vs. 80.57±4.09%; p<0.01) and naloxone (53.94±4.20% vs. 73.89±7.26%; p<0.05). Yohimbine (p>0.05) and propranolol (p>0.05) however did not have any significant effect on the contractile activity of the extract.
The freeze dried extract of B. biternata possess significant antidiarrheal activity in both in vitro and in vivo models which appears to be mediated by modulating both the intestinal motility as well as the secretory activity. The results of this study also validate its traditional use as an antidiarrheal remedy.
腹泻仍是五岁以下儿童的主要杀手之一。传统止泻疗法在资源匮乏地区构成了一种潜在可行的新型低成本有效治疗来源。因此，迫切需要对这些疗法进行科学评估。
本研究旨在调查冻干的鬼针草（Bidens biternata）的体内和体外止泻活性，鬼针草是传统阿育吠陀医学中用于治疗腹泻的一种草药。
在蓖麻油试验中，将二十（20）只成年斯普拉格-道利大鼠随机分为阴性对照组（生理盐水，n = 5）、阳性对照组（5mg/kg洛哌丁胺，n = 5）和两个试验组。低剂量试验组接受200mg/kg鬼针草提取物（n = 5），而高剂量试验组接受400mg/kg鬼针草提取物（n = 5）。在给予相应治疗一小时后，给动物灌胃蓖麻油（4ml/kg），然后在四（4）小时后测定排出的粪便总质量。在炭末试验中，将十五（15）只斯普拉格-道利大鼠随机分为对照组（口服5ml/kg生理盐水，n = 5）、阳性对照组（腹腔注射0.1mg/kg硫酸阿托品，n = 5）和试验组（400mg/kg鬼针草提取物，n = 5）。在给予各种治疗三十（30）分钟后，通过口服灌胃给每只大鼠给予炭末。在喂食后三十分钟处死动物后，测定炭末从幽门移动的距离。在肠积液试验中，将二十（20）只斯普拉格-道利大鼠随机分为对照组（5% v/v乙醇溶于生理盐水中，n = 5）、阳性对照组（5mg/kg洛哌丁胺，n = 5）和试验组（400mg/kg鬼针草提取物，n = 5）。对于每组，在治疗后立即给予前列腺素E（PGE2）（100μg/kg）。然后在半小时后处死动物并测定小肠内容物的体积。研究了不同浓度的鬼针草提取物（0.5、1.0、2.0、3.0和5.0mg/ml）对空肠收缩的影响，并使用实验数据构建剂量-反应曲线，然后确定ED50剂量。还研究了坦索罗辛（α1肾上腺素能阻滞剂）、育亨宾（α2肾上腺素能阻滞剂）、普萘洛尔（β肾上腺素能阻滞剂）和纳洛酮（μ阿片受体阻滞剂）对提取物收缩活性的影响。实验数据以平均值±平均标准误差（SEM）表示，然后使用单因素方差分析进行分析，在有显著性差异的情况下（设定为p<0.05），随后进行Tukey事后检验。
冻干的鬼针草提取物在蓖麻油诱导的腹泻模型中具有显著的止泻作用（p<0.01），在400mg/kg剂量水平观察到最高活性（1.66±0.81g对对照组4.54±0.51g，p = 0.01）。与对照组相比，鬼针草提取物在炭末试验中对肠道运动有显著影响（43.61±4.42%对60.54±3.33%：p<0.05）。鬼针草提取物对PGE2诱导的肠积液有显著影响（3.06±0.07ml对4.74±0.10ml；p<0.001）。冻干的鬼针草提取物对离体兔空肠的收缩性有显著的负性影响（p<0.001）。坦索罗辛（53.94±4.20%对80.57±4.09%；p<0.01）和纳洛酮（53.94±4.20%对73.89±7.26%；p<0.05）显著减弱了提取物的作用。然而育亨宾（p>0.05）和普萘洛尔（p>0.05）对提取物的收缩活性没有任何显著影响。
冻干的鬼针草提取物在体外和体内模型中均具有显著的止泻活性，这似乎是通过调节肠道运动以及分泌活性来介导的。本研究结果也证实了其作为止泻疗法的传统用途。
