Feeding of 1-Kestose Induces Glutathione-S-Transferase Expression in Mouse Liver

Functional food ingredients, including prebiotics, have been increasingly developed for human health. The improvement of the human intestinal environment is one of their main targets. Fructooligosaccarides (FOS) are oligosaccharide fructans that are well studied and commercialized prebiotics. 1-Kestose, one of the components of FOS, is considered to be a key prebiotic component in FOS. However, to our knowledge, no studies have been reported on the physiological efficacy of 1-Kestose regarding its anti-oxidative activity. In the present study, we examined the effects of dietary 1-Kestose on gene expression of antioxidative enzymes in the liver, kidney and epididymal adipose tissue of mice by quantitative RT-PCR (qRT-PCR). We demonstrated that a 1-Kestose-rich diet increased mRNA and enzymatic activity levels of glutathione-S-transferase (GST) in mouse liver. These results suggest the possibility that dietary 1-Kestose as a prebiotic may enhance antioxidative activity in mice

Dinuclear Bridging Bidentate Zinc/Stearate Complex in Sulfur Cross-Linking of Rubber

An essential structure of the intermediate generated from zinc oxide and stearic acid during sulfur cross-linking reaction of isoprene rubber is proposed using time-resolved zinc K-edge X-ray absorption fine structure and infrared spectroscopies <i>in situ.</i> The structure is dominantly a bridging bidentate zinc/stearate complex, the molar ratio of the zinc ion to stearate and the coordination number of which are unexpectedly 1:1 and 4, respectively. Combination with a density functional calculation for identifying the intermediate predominantly suggests that its most possible structure is (Zn₂(μ-O₂CC₁₇H₃₅)₂)²⁺(OH^–)₂·XY, where X and Y are water and/or a rubber segment. This intermediate has been unknown despite the long history of rubber science and technology. The newly observed zinc/stearate complex may play a role to accelerate the sulfur cross-linking reaction of rubber like an enzyme because of the high Lewis activity of the zinc ion

Thioester‐Based Coupled Fluorogenic Assays in Microdevice for the Detection of Single‐Molecule Enzyme Activities of Esterases with Specified Substrate Recognition

Abstract Single‐molecule enzyme activity assay is a platform that enables the analysis of enzyme activities at single proteoform level. The limitation of the targetable enzymes is the major drawback of the assay, but the general assay platform is reported to study single‐molecule enzyme activities of esterases based on the coupled assay using thioesters as substrate analogues. The coupled assay is realized by developing highly water‐soluble thiol‐reacting probes based on phosphonate‐substituted boron dipyrromethene (BODIPY). The system enables the detection of cholinesterase activities in blood samples at single‐molecule level, and it is shown that the dissecting alterations of single‐molecule esterase activities can serve as an informative platform for activity‐based diagnosis

Transcutaneous Carbon Dioxide Induces Mitochondrial Apoptosis and Suppresses Metastasis of Oral Squamous Cell Carcinoma <i>In Vivo</i>

<div><p>Squamous cell carcinoma (SCC) is the main histological type of oral cancer. Its growth rate and incidence of metastasis to regional lymph nodes is influenced by various factors, including hypoxic conditions. We have previously reported that transcutaneous CO₂ induces mitochondrial apoptosis and decreases lung metastasis by reoxygenating sarcoma cells. However, previous studies have not determined the sequential mechanism by which transcutaneous CO₂ suppresses growth of epithelial tumors, including SCCs. Moreover, there is no report that transcutaneous CO₂ suppresses lymphogenous metastasis using human cell lines xenografts. In this study, we examined the effects of transcutaneous CO₂ on cancer apoptosis and lymphogenous metastasis using human SCC xenografts. Our results showed that transcutaneous CO₂ affects expressions of PGC-1α and TFAM and protein levels of cleavage products of caspase-3, caspase-9 and PARP, which relatives mitochondrial apoptosis. They also showed that transcutaneous CO₂ significantly inhibits SCC tumor growth and affects expressions of HIF-1α, VEGF, MMP-2 and MMP-9, which play essential roles in tumor angiogenesis, invasion and metastasis. In conclusion, transcutaneous CO₂ suppressed tumor growth, increased mitochondrial apoptosis and decreased the number of lymph node metastasis in human SCC by decreasing intra-tumoral hypoxia and suppressing metastatic potential with no observable effect <i>in vivo</i>. Our findings indicate that transcutaneous CO₂ could be a novel therapeutic tool for treating human SCC.</p></div

Procedure for administering transcutaneous CO₂ in animal model of human SCC.

<p>The area of skin around the implanted tumor was covered with CO₂ hydrogel and sealed with a polyethylene bag, through which 100% CO₂ gas was administered. Treatment commenced 7 days after HSC-3 cell implantation, and was performed twice a week for 3 weeks.</p

The effect of transcutaneous CO₂ on HSC-3 tumor growth.

<p>Tumor growth (A) and body weight (B) was monitored for 4 weeks in the CO₂-treated and control groups (*P<0.05).</p

The effect of transcutaneous CO₂ on HSC-3 cell apoptotic pathway.

<p>(A) The mRNA expressions of PGC-1α and TFAM gene were evaluated using real-time PCR (*P<0.05). (B) Mitochondrial DNA (mtDNA) content was also measured; differences were not statically significant. (C) Immunoblot analysis of expressions of the cleavage products of caspase-3, caspase-9 and PARP. β-actin was used as an endogenous loading control. (D) At the end of experiment, the numbers of apoptotic cells in tumors of both groups were assessed by FACS.</p

The effect of transcutaneous CO₂ on the metastatic potential of HSC-3.

<p>(A) The mRNA expressions of VEGF, MMP-2 and MMP-9 gene were measured using real-time PCR (*P<0.05). (B) Immunohistochemical staining for HIF-1α, VEGF, MMP-2 and MMP-9 in implanted tumors from both groups.</p