Effect of trichosanthin and momorcharins on isolated rat hepatocytes

Trichosanthin suppresses the proliferation of glioma cells by inhibiting LGR5 expression and the Wnt/β-catenin signaling pathway

Studies have indicated that trichosanthin (TCS), a bioactive protein extracted and purified from the tuberous root of Trichosanthes kirilowii (a well-known traditional Chinese medicinal plant), produces antitumor effects on various types of cancer cells. However, the effects of TCS on glioma cells are poorly understood. The objective of this study was to investigate the antitumor effects of TCS on the U87 and U251 cell lines. The in vitro effects of TCS on these two cell lines were determined using a Cell Counting Kit-8 (CCK-8) assay, Annexin V-FITC staining, DAPI staining, Transwell assays, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assays, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacar-bocyanine iodide (JC-1) staining and western blotting, which was utilized to assess the expression of leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) and key proteins in the Wnt/β-catenin signaling pathway. Our data indicated that TCS inhibited the proliferation of glioma cells in a dose- and time-dependent manner and played a role in inhibiting glioma cell invasion and migration. Additional investigation revealed that the expression levels of LGR5 and of key proteins in the Wnt/β-catenin signaling pathway were markedly decreased after TCS treatment. The results suggest that TCS may induce apoptosis in glioma cells by targeting LGR5 and repressing the Wnt/β-catenin signaling pathway. In the future, in vivo experiments should be conducted to examine the potential use of this compound as a novel therapeutic agent for gliomas.

Anti-diabetic properties and phytochemistry of Momordica charantia L. (Cucurbitaceae)

Unripe fruit, seeds and aerial parts of Momordica charantia Linn. (Cucurbitaceae) have been used in various parts of the world to treat diabetes. Oral administration of the fruit juice or seed powder causes a reduction in fasting blood glucose and improves glucose tolerance in normal and diabetic animals and in humans. Animal and in vitro data support both insulin secretagogue and insulinomimetic activity of the fruit. However, enhanced insulin levels in vivo in response to its administration have not been observed. Although a wide range of compounds have been isolated from Momordica charantia, notably steroidal compounds and proteins, the orally active antidiabetic principle has not been adequately identified. A polypeptide, p-insulin, produces hypoglycaemic effects in humans and animals on subcutaneous injection, but oral activity is questionable. Other reported hypoglycaemic principles from Momordica charantia include the sterol glucoside mixture charantin (fruit) and the pyrimidine nucleoside vicine (seeds). However these are only effective at doses too high to account for all the activity of the plant extract. Principal toxicity of Momordica charantia in animals is to the liver and reproductive system. These effects have not been reported in humans despite widespread use of the fruit medicinally and as a vegetable.