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This study was designed to investigate the oil entrapment and systemic oil absorption-reducing activities of chitosan. High-molecular-weight chitosan formed gel aggregates with oil and bile salts in vitro. The oil/chitosan ratio and the molecular weight of chitosan were optimized for the in vivo study, and a molecular weight >100,000 was effective in reducing the oil contamination of mouse fur. The oil/chitosan weight ratio required for effective oil entrapment was less than 13 and 5 in the in vitro and in vivo experiments, respectively. Chitosan administration was most effective during meals, and high-molecular-weight chitosan could trap and facilitate the reduction of systemic absorption of oil droplets separated by orlistat. The activity of the lipase inhibitor was not altered by chitosan as evidenced by thin layer chromatography, and orlistat was not absorbed systemically by the co-administration of chitosan., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Here we demonstrate that JNK3 can phosphorylate Smac. Smac phosphorylation attenuates its ability to activate apoptosome activity in HeLa S-100 cell lysates. Addition of the X-linked inhibitor of apoptosis protein (XIAP) to the S-100 markedly suppresses apoptosome activity, and this suppressive effect of XIAP is neutralized by adding unphosphorylated Smac, but not phosphorylated Smac. Furtherover, JNK3-mediated phosphorylation of Smac markedly attenuates the interaction between Smac and XIAP, as measured by BIACORE assays and non-denaturing gel shift assays. When JNK3 activity is down-regulated in etoposide-induced HeLa cells by transiently overexpressing a dominant negative version of JNK3 (DN-JNK3), the caspase-3 activity as well as PARP cleavages are markedly enhanced. And the interaction of Smac with XIAP also increases by down-regulating JNK3 activity under the same conditions. These results suggest that JNK3 activity can attenuate the progression of apoptosis through a novel mechanism of action, the down-regulation of interaction between Smac and XIAP.