Andrographolide, a labdane diterpenoid isolated from Andrographis paniculata, putatively functions through covalent inhibition of NF-κB, a transcription factor that modulates tumor survival and metastasis. Previous studies have found that functionalization of the C-19 hydroxyl alters the primary mode of action from inhibition of NF-κB to the modulation of the Wnt1/β-catenin signaling pathway. Here, we synthesized a series of twelve C-19 trityl and silyl ether analogs, including three novel substituted trityl analogs and four novel substituted silyl analogs of andrographolide.
View Article and Find Full Text PDFThe enteric nervous system, the largest division of the peripheral nervous system, is derived from vagal neural crest cells that invade and populate the entire length of the gut to form diverse neuronal subtypes. Here, we identify a novel population of neurons within the enteric nervous system of zebrafish larvae that express the transgenic marker ptf1a:GFP within the midgut. Genetic lineage analysis reveals that enteric ptf1a:GFP(+) cells are derived from the neural crest and that most ptf1a:GFP(+) neurons express the neurotransmitter 5HT, demonstrating that they are serotonergic.
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