Both adaptive and deleterious responses of cells to ethanol are likely triggered by short-term interactions of the cells with ethanol. Many studies have demonstrated the direct effect of ethanol on growth factor-stimulated cell proliferation. Using Swiss 3T3 cells whose growth was inhibited by ethanol in a concentration-dependent manner, we further investigated the molecular mechanisms of acute ethanol treatment by examining its effect on EGF-and PDGF-mediated cellular signaling systems for the mitogenic function. Tyrosine autophosphorylation of the growth factor receptors was partially prevented by ethanol in intact cells. When ethanol was included before or after EGF stimulation, no effect on the receptor signaling was observed. Here we also report that ethanol inhibits activation of ERK induced by both EGF and PDGF. EGF-induced JNK activation was reduced but PDGF-induced rapid JNK activation was delayed by the addition of ethanol. The balance between its inhibitory and stimulatory effect on the signaling molecules might determine the rate of cell growth.
We report the cytotoxicity of the ginseng saponin metabolite, Compound K (20‐O‐D‐glucopyranosyl‐20(S)‐protopanaxadiol, IH901) on various human leukemia cell lines. Compound K had the most effect on U937, a human monocytic leukemia cell line among the tested cell lines. Compound K‐treated U937 cells showed characteristics of apoptosis: an exposure of phosphatidylserine from the inner cell membrane to the outer cell membrane, the formation of apoptotic bodies and DNA fragmentation. Compound K induced apoptosis by up‐regulating Bax, disrupting the mitochondrial membrane potential, and by activating caspase 9 and caspase 3. Therefore, we suggest that Compound K inhibits U937 cell growth by inducing apoptosis through the up‐regulation of Bax and caspase activation.
Red variants of S. japonicus show unique ecological characteristics and are indigenous to Jeju Island in South Korea. Various biological activities of red sea cucumber extracts (RSCEs) were evaluated. In comparison with positive controls, anti-oxidant activity of RSCEs was very low. In HL-60 and HT-29 cells, chloroform and ethyl acetate (EtOAc) fractions showed higher than 80 and 60% growth inhibition, respectively. Nuclear condensation and increased pro-apoptotic signaling revealed that RSCEs triggered apoptosis. EtOAc fractions also showed strong anti-inflammatory effects at sub-lethal concentrations in lipolysaccharide-stimulated RAW264.7 cells and suppressed more than 90% of nitric oxide (NO) and prostaglandin 2 productions at 50 µg/mL by inhibiting inducible NO synthase and cydooxygenase-2. Water-soluble fractions showed good antibacterial effects against Staphylococcus aureus and Staphylococcus epidermidis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.