Das B, Tandon V, Saha N
Department of Zoology, North Eastern Hill University, Shillong-793022, India.
Parasitology. 2007 Sep;134(Pt 10):1457-63. doi: 10.1017/S003118200700282X. Epub 2007 Apr 24.
Cyclic GMP (cGMP) is responsible for various cellular functions including signal pathways and it acts as a mediator for nitric oxide (NO). In order to evaluate the anthelmintic efficacy of the plant-derived isoflavones, the crude peel extract of Flemingia vestita and pure genistein were tested with respect to the activity of nitric oxide synthase (NOS), NO efflux and the cGMP concentration in Rallietina echinobothrida, the cestode parasite of domestic fowl. For comparison, the parasites were also treated with genistein (the major isoflavone present in the crude peel extract), sodium nitroprusside (SNP), a known NO donor, and praziquantel (PZQ), the reference drug. At the time of onset of paralysis in the parasite, the activity of NOS showed a significant increase (35-46%) and a 2-fold increase of NO efflux into the incubation medium in the treated worms in comparison to the respective controls. The cGMP concentration in the parasite tissue increased by 46-84% in the treated test worms in comparison to the controls. The results show that the isoflavones, genistein in particular, from the crude peel extract of F. vestita influence the cGMP concentration in the parasite tissue, which plays a major role in the downstream signal pathways.
环磷酸鸟苷（cGMP）负责多种细胞功能，包括信号通路，它作为一氧化氮（NO）的介质发挥作用。为了评估植物来源的异黄酮的驱虫效果，对家鸡绦虫寄生虫棘盘瑞利绦虫（Rallietina echinobothrida）的一氧化氮合酶（NOS）活性、NO流出量和cGMP浓度进行了测试，使用了绒毛千斤拔（Flemingia vestita）的粗皮提取物和纯染料木黄酮。作为比较，还使用染料木黄酮（粗皮提取物中的主要异黄酮）、硝普钠（SNP，一种已知的NO供体）和吡喹酮（PZQ，参考药物）对寄生虫进行处理。在寄生虫开始麻痹时，与各自的对照组相比，处理后的蠕虫中NOS活性显著增加（35 - 46%），并且向孵育培养基中流出的NO增加了2倍。与对照组相比，处理后的受试蠕虫中寄生虫组织中的cGMP浓度增加了46 - 84%。结果表明，来自绒毛千斤拔粗皮提取物的异黄酮，特别是染料木黄酮，会影响寄生虫组织中的cGMP浓度，而cGMP在下游信号通路中起主要作用。
