Department of Studies in Biotechnology, University of Mysore, Mysore, Karnataka, India.
J Ethnopharmacol. 2013 Oct 7;149(3):737-44. doi: 10.1016/j.jep.2013.07.034. Epub 2013 Aug 7.
Preparations of Orthosiphon diffusus (Benth.) have been used by folk medicinal practitioners in the Western Ghats of India for treating inflammation, hepatitis and jaundice for many years and their effectiveness is widely acclaimed among the tribal communities.
To evaluate the mechanisms behind the antioxidant and hepatoprotective potential of Orthosiphon diffusus methanol active fraction (MAF) using in vivo (rat) and in vitro (cell culture) models.
Neutralization of CCl4-induced hepatotoxicity by MAF was evaluated in rats. Towards this, serum levels of hepatic injury markers (lactate dehydrogenase and alkaline phosphatase), antioxidant enzymes in the liver homogenates, and histological examination were performed. In in vitro studies, mechanisms of neutralization of H2O2-induced toxicity by MAF using MTT, Comet assay and up-regulation of antioxidant enzymes at genetic level (RT-PCR) was performed in HepG2 cells.
Rats pre-treated with Orthosiphon diffusus MAF demonstrated significantly reduced levels of serum LDH (1.3-fold, p<0.05) and ALP (1.6-fold, p<0.05). Similarly, multiple dose MAF administration demonstrated significantly enhanced levels (p<0.05) of antioxidant enzymes in the liver homogenates. Histological analysis revealed complete neutralization of CCl4-induced liver injury by the extract. The in vitro studies demonstrated that, pre-treatment of MAF effectively prevented H2O2-induced oxidative stress, genotoxicity and significantly enhanced (~6-fold, p<0.01) expression of genes for antioxidant enzymes.
Orthosiphon diffusus MAF demonstrated significant hepatoprotection against CCl4-induced hepatotoxicity by antioxidant mechanisms comparable to silymarin. H2O2-induced oxidative stress was completely neutralized by MAF through enhanced expression of genes for antioxidant enzymes. Therefore, this study validates the use of Orthosiphon diffusus by folk medicinal practitioners in India. Further, MAF of Orthosiphon diffusus can serve as a strong candidate for the development of herbal hepatoprotective agents.
多年来，印度西高止山脉的民间医学从业者一直使用罗托斯菲恩扩散（本）制剂来治疗炎症、肝炎和黄疸，其疗效在部落社区中广受赞誉。
使用体内（大鼠）和体外（细胞培养）模型评估罗托斯菲恩扩散甲醇活性部分（MAF）抗氧化和保肝作用的潜在机制。
用 MAF 中和 CCl4 诱导的肝毒性，在大鼠中进行评估。为此，进行了血清肝损伤标志物（乳酸脱氢酶和碱性磷酸酶）、肝匀浆中的抗氧化酶以及组织学检查。在体外研究中，使用 MTT、彗星试验和在遗传水平上上调抗氧化酶（RT-PCR），在 HepG2 细胞中研究 MAF 中和 H2O2 诱导的毒性的机制。
用 Orthosiphon diffusus MAF 预处理的大鼠，血清 LDH（1.3 倍，p<0.05）和 ALP（1.6 倍，p<0.05）水平明显降低。同样，多次给予 MAF 后，肝匀浆中的抗氧化酶水平显著升高（p<0.05）。组织学分析表明，提取物完全中和了 CCl4 诱导的肝损伤。体外研究表明，MAF 的预处理可有效预防 H2O2 诱导的氧化应激、遗传毒性，并显著增强抗氧化酶基因的表达（~6 倍，p<0.01）。
MAF 通过与水飞蓟素相当的抗氧化机制，对 CCl4 诱导的肝毒性表现出显著的保肝作用。MAF 完全中和了 H2O2 诱导的氧化应激，通过增强抗氧化酶基因的表达。因此，本研究验证了印度民间医学从业者使用 Orthosiphon diffusus 的合理性。此外，Orthosiphon diffusus 的 MAF 可以作为开发草药保肝剂的有力候选物。
