R&D Centre, Natural Remedies Pvt. Ltd., Bangalore, Karnataka, India.
J Ethnopharmacol. 2013 Jan 30;145(2):581-6. doi: 10.1016/j.jep.2012.11.033. Epub 2012 Dec 7.
Glycyrrhiza glabra Linn. is regarded useful for peptic ulcer in traditional systems of medicine in India and Helicobacter pylori has been considered as one of the causative factors for peptic ulcer. Aim of the present study is to evaluate the anti-Helicobacter pylori action of GutGard(®), a flavonoid rich extract of Glycyrrhiza glabra and further to elucidate the possible mechanisms of its anti-Helicobacter pylori action.
Agar dilution and microbroth dilution methods were used to determine the minimum inhibitory concentration of GutGard(®) against Helicobacter pylori. Protein synthesis, DNA gyrase, dihydrofolate reductase assays and anti-adhesion assay in human gastric mucosal cell line were performed to understand the mechanisms of anti-Helicobacter pylori activity of GutGard(®).
GutGard(®) exhibited anti-Helicobacter pylori activity in both agar dilution and microbroth dilution methods. Glabridin, the major flavonoid present in GutGard(®) exhibited superior activity against Helicobacter pylori while glycyrrhizin did not show activity even at 250 μg/ml concentration. In protein synthesis assay, GutGard(®) showed a significant time dependent inhibition as witnessed by the reduction in (35)S methionine incorporation into Helicobacter pylori ATCC 700392 strain. Additionally, GutGard(®) showed a potent inhibitory effect on DNA gyrase and dihydrofolate reductase with IC(50) value of 4.40 μg/ml and 3.33 μg/ml respectively. However, the extract did not show significant inhibition on the adhesion of Helicobacter pylori to human gastric mucosal cell line at the tested concentrations.
The present study shows that, GutGard(®) acts against Helicobacter pylori possibly by inhibiting protein synthesis, DNA gyrase and dihydrofolate reductase.
在印度的传统医学体系中，甘草被认为对胃溃疡有疗效，而幽门螺杆菌已被认为是胃溃疡的致病因素之一。本研究旨在评估 GutGard（®）——一种富含甘草黄酮的提取物对幽门螺杆菌的抑制作用，并进一步阐明其抗幽门螺杆菌作用的可能机制。
采用琼脂稀释法和微量肉汤稀释法测定 GutGard（®）对幽门螺杆菌的最小抑菌浓度。通过人胃黏膜细胞系的蛋白质合成、DNA 回旋酶、二氢叶酸还原酶测定和抗黏附试验来了解 GutGard（®）抗幽门螺杆菌活性的机制。
GutGard（®）在琼脂稀释法和微量肉汤稀释法中均表现出抗幽门螺杆菌活性。在 GutGard（®）中主要的黄酮类化合物——甘草苷对幽门螺杆菌表现出较强的活性，而甘草酸即使在 250μg/ml 浓度下也没有活性。在蛋白质合成试验中，GutGard（®）表现出明显的时间依赖性抑制作用，表现为（35）S 甲硫氨酸掺入幽门螺杆菌 ATCC 700392 株的减少。此外，GutGard（®）对 DNA 回旋酶和二氢叶酸还原酶具有很强的抑制作用，IC50 值分别为 4.40μg/ml 和 3.33μg/ml。然而，在测试浓度下，该提取物对幽门螺杆菌与人胃黏膜细胞系的黏附没有明显的抑制作用。
本研究表明，GutGard（®）可能通过抑制蛋白质合成、DNA 回旋酶和二氢叶酸还原酶来抑制幽门螺杆菌。
