Parkia speciosa Hassk is a traditional medicinal plant with strong antioxidant and hypoglycemic properties. This study aims to investigate the total phenolic content, antioxidant, cytotoxic and antiangiogenic effect of eight extracts from P. speciosa empty pods. The extracts were found to contain high levels of total phenols and demonstrated strong antioxidant effect in DPPH scavenging test. In rat aortic rings, P. speciosa extracts significantly inhibited the microvessel outgrowth from aortic tissue explants by more than 50%. The antiangiogenic activity was further confirmed by tube formation on matrigel matrix involving human endothelial cells. Cytotoxic effect was evaluated by XTT test on endothelial cells as a model of angiogenesis versus a panel of human cancer and normal cell lines. Basically the extracts did not show acute cytotoxicity. Morphology examination of endothelial cells indicated induction of autophagy characterized by formation of plenty of cytoplasmic vacuoles. The extracts were found to work by decreasing expression of vascular endothelial growth factor in endothelial cells.
Deregulated cell signaling pathways result in cancer development. More than one signal transduction pathway is involved in colorectal cancer pathogenesis and progression. Koetjapic acid (KA) is a naturally occurring seco-A-ring oleanene triterpene isolated from the Sandoricum koetjape stem bark. We report the cellular and molecular mechanisms of anticancer activity of KA towards human colorectal cancer. The results showed that KA induces apoptosis in HCT 116 colorectal carcinoma cells by inducing the activation of extrinsic and intrinsic caspases. We confirmed that KA-induced apoptosis was mediated by DNA fragmentation, nuclear condensation and disruption in the mitochondrial membrane potential. Further studies on the effect of KA on cancer pathways show that the compound causes down-regulation of Wnt, HIF-1α, MAP/ERK/JNK and Myc/Max signaling pathways and up-regulates the NF-κB signaling pathway. The result of this study highlights the anticancer potential of KA against colorectal cancer.
Angiogenesis, the formation of new blood vessels, has become an important target in cancer therapy. Angiogenesis plays an important role in tumor growth and metastasis. Koetjapic acid (KA) is a seco-A-ring oleanene triterpene isolated from S. koetjape. The solvent extract of this plant species was shown previously to have strong antiangiogenic activity; however the active ingredient(s) that conferred the biological activity and the mode of action was not established. Given the high concentration of KA in S. koetjape, an attempt has been made in this study to investigate the antiangiogenic properties of KA.