ABSTRACT
Background: Curcumin (CUR) and tetrahydrocurcumin (THC) inhibits tumor angiogenesis. It is suggested that tumor progress may be related to the pathway of extracellular signal-regulated kinase 1/2 (ERK1/2) and serine/ threonine kinase AKT, but the mechanism remains unclear. Objective: Investigate the effects of CUR and THC on the expression of ERK1/2 and AKT in hepatocellula carcinoma (HepG2)-induced tumors in nude mice. Methods: The curcuminoid mixture was obtained from the rhizomes of Curcuma longa, which was subjected to silica gel column chromatography to afford CUR as the major constituent. THC was prepared by hydrogenation of curcumin with palladium on charcoal as a catalyst. HepG2-implanted nude mice model was used to study of angiogenesis and tumor progression. Expressions of phospho-ERK1/2 (p-ERK1/2) and phopho-AKT (p-AKT) in HepG2-implated tissue were measured by immunohistochemistry. Tumor area, area of expression and expression ratio of pERK1/2 and p-AKT were determined. Results: Increases in p-ERK1/2 and p-AKT expression in HepG2 group was related to changes in tumor growth in control, CUR, and THC groups. THC-treatment could attenuate the p-ERK1/2, p-AKT expression, tumor area, and ratio of expression in HepG2-implanted nude mice significantly, compared to CUR-treatment. Conclusion: HepG2-induced tumor progression may be inhibited by THC in part through the inhibition of mitogen-activated protein kinase (MEK)/ERK and phosphoinositide 3-kinase (PI3K)/AKT.
ABSTRACT
Effects of elephant garlic (Allium ampeloprasum) volatile oil (GVO) and trichothecene (T-2) toxin were studied in Swiss albino mice. The animals were 1) topically applied GVO, 2) topically applied T-2 toxin, 3) topically applied GVO followed by T-2 toxin (GVO/T-2), and 4) T-2 toxin application followed by GVO (T-2/GVO) on the right footpad. All animals were observed by Langerhans cell enumeration and pathological changes of the footpad on days 1, 3, 5 and 7. The number of Langerhans cells in the GVO treated group (1,097 +/- 33/mm2 to 1,624 +/- 19/mm2) was not significantly different when compared with the corresponding control left footpad (1,143 +/- 33/mm2 to 1,674 +/- 21/mm2). Langerhans cells density in T-2 toxin treated group (629 +/- 29/mm2to 1,090 +/- 31/mm2) was reduced by 20-35% of the opposite control footpad (962 +/- 40/mm2 to 1,392 +/- 29/mm2). Furthermore, GVO/T-2 and T-2/GVO treated mice showed a decrease in Langerhans cell number than a single T-2 toxin treated group. While Langerhans cells in T-2 toxin, GVO/T-2 and T-2/GVO groups revealed a smaller cell size with shortening dendritic processes when compare to the normal control group. Histopathological findings of the footpad skin in T-2 toxin treated group revealed epidermal desquamation and necrosis with edema and inflammatory cells infiltration. While GVO/T-2 and T-2/GVO showed a similar sequence but a lesser severe degree. These findings suggested that GVO both in pre- and posttreatment could protect T-2 toxin induced epidermal damage in a mouse footpad.