Effect of a 0.6% energy trans fatty acid intake on serum cholesterol concentrations in healthy young Japanese subjects

A randomized crossover study in healthy young Japanese showed no significant effects of a 0.6% energy trans fatty acid (TFA) intake on the serum cholesterol concentrations and parameters of glucose metabolism. The results indicate that TFAs at this dietary level may have no adverse metabolic effects on healthy young Japanese.     

Increased plasma concentration of epigallocatechin in mice after orally administering a green tea (Camellia sinensis L.) extract supplemented by steamed rice

We attempted to improve the bioavailability of green tea catechins by using food ingredients. The catechin bioavailability of a green tea extract administered to mice was significantly (p<0.05) increased by supplementing with steamed rice. This enhanced bioavailability was due to the increased concentration of plasma non-gallated catechins, especially epigallocatechin (EGC).     

Effect of green tea powder (<Emphasis Type="Italic">Camellia sinensis</Emphasis> L. cv. Benifuuki) particle size on <Emphasis Type="Italic">O</Emphasis>-methylated EGCG absorption in rats; The Kakegawa Study

Tea polyphenols, e.g., (-)-epigallocatechin-3-O-(3-O-methyl gallate (EGCG3”Me), (-)-epigallocatechin-3-O-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin-3-O-gallate (ECG), and (-)-epicatechin (EC), are believed to be responsible for the beneficial effects of tea. ‘Benifuuki’, a tea (Camellia sinensis L.) cultivar grown in Japan, is rich in the anti-allergic molecule epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3”Me). Pulverized Benifuuki green tea powder (BGP) is more widely distributed than leaf tea in Japan. Japanese people mix their pulverized tea with water directly, whereas it is common to drink leaf tea after extraction. However, few studies of the effects of BGP particle size on polyphenol bioavailability have been performed. This study was conducted to investigate the absorption of catechins in rats after the intragastric administration of Benifuuki green tea. Therefore, we assessed the plasma concentrations of catechins following the ingestion of BGP with different mean particle sizes (2.86, 18.6, and 76.1 μm) or Benifuuki green tea infusion (BGI) as a control in rats. The bioavailabilities of EGCG3”Me, EGCG, ECG, EGC, and EC were analyzed after the oral administration of a single dose of Benifuuki green tea (125 mg/rat) to rats. The plasma concentrations of tea catechins were determined by HPLC analysis combined with of electrochemical detection (ECD) using a coulometric array. The AUC (area under the drug concentration versus time curve; min μg/mL) of ester-type catechins (EGCG3”Me, EGCG, and ECG) for the BGP 2.86 μm were significantly higher than those in the infusion and 18.6 and 76.1 μm BGP groups, but the AUC of free-type catechins (EGC and EC) showed no differences between these groups. Regarding the peak plasma level of EGCG3”Me adjusted for intake, BGP 2.86 μm and BGI showed higher values than the BGP 18.6 and 76.1 μm groups, and the peak plasma levels of the other catechins displayed the same tendency. The present study demonstrates that the bioavailability of ester-type catechins (EGCG and ECG) can be improved by reducing the particle size of green tea, but the plasma level of EGCG3”Me in the BGI group was similar to that in the BGP 2.86 μm group. This result suggests that drinking Benifuuki green tea with a particle size of around 2 μm would deliver the anti-allergic EGCG3”Me and the anti-oxidant EGCG efficiently.     

Generation of Rejuvenated Antigen-Specific T Cells by Reprogramming to Pluripotency and Redifferentiation

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Highlights? Reprogramming of antigen-specific T cells to generate iPSCs (T-iPSCs) ? Redifferentiation of CD8⁺ T cells, with original antigen specificity, from T-iPSCs ? Newly differentiated T cells show high proliferation and elongated telomeres ? T cell antigen-specific cytotoxicity is maintained     

Development of dual functional SPECT/fluorescent probes for imaging cerebral β-amyloid plaques

The imaging of β-amyloid (Aβ) aggregates in the brain may lead to the early detection of Alzheimer’s disease (AD) and monitoring of the progression and effectiveness of treatment. The purpose of this study was to develop dual modality SPECT and fluorescent probes based on boron dipyrromethane (BODIPY) as a core structure. We designed and synthesized an ¹²⁵I-labeled derivative of BODIPY (BODIPY7). BODIPY7 had a K_i value of 108 nM for Aβ(1–42) aggregates and exhibited peaks of absorption/emission at 606/613 nm. It detected Aβ plaques in sections of brain tissue from an animal model of AD and displayed low uptake in the brain and high uptake in the liver in normal mice. Although additional modifications of the BODIPY scaffold are necessary to improve brain uptake, these results should aid the development of dual functional SPECT/fluorescent probes for the imaging of Aβ plaques in the brain.     

Effects of phosphatidylethanolamine N-methyltransferase on phospholipid composition, microvillus formation and bile salt resistance in LLC-PK1 cells

Bile salts are potent detergents and can disrupt cellular membranes, which causes cholestasis and hepatocellular injury. However, the mechanism for the resistance of the canalicular membrane against bile salts is not clear. Phosphatidylethanolamine (PE) is converted to phosphatidylcholine (PC) in the liver by phosphatidylethanolamine N-methyltransferase (PEMT). In this study, to investigate the effect of PEMT expression on the resistance to bile salts, we established an LLC-PK1 cell line stably expressing PEMT. By using enzymatic assays, we showed that the expression of PEMT increased the cellular PC content, lowered the PE content, but had no effect on the sphingomyelin content. Consequently, PEMT expression led to reductions in PE/PC and sphingomyelin/PC ratios. Mass spectrometry demonstrated that PEMT expression increased the levels of PC species containing longer acyl chains and almost all ether-linked PC species. PEMT expression enhanced the resistance to duramycin and lysenin, suggesting decreased ratios of PE and sphingomyelin in the apical membrane, respectively. In addition, SEM revealed that PEMT expression increased the diameter of microvilli. The expression of PEMT resulted in reduced resistance to unconjugated bile salts, but surprisingly in increased resistance to conjugated bile salts, which might be attributable to modifications of the phospholipid composition and/or structure in the apical membrane. Because most bile salts exist as conjugated forms in the bile canaliculi, PEMT may be important in the protection of hepatocytes from bile salts and in cholestatic liver injury.     

Redescription of Piguetiella denticulata (Annelida, Clitellata, Naididae) from Japan and the Russian Far East, with a description of the genital organs in the species

A naidid oligochaete, Piguetiella denticulata Liang and Xie (Invertebrates of Wuling Mountains area, Southwestern China, pp 383–394, 1997), is redescribed based on new material from Japan and the Russian Far East, and its generic position is verified by an examination of the reproductive organs. P. denticulata closely resembles P. michiganensis in lacking eyes and dorsal hair chaetae, but it is distinguished from the latter by having intermediate teeth on both its dorsal and ventral crotchets. In Japan, P. denticulata is widely distributed and often abundant in mountain streams with sandy and gravelly bottoms.     

Smoking Cessation Increases Short-Term Risk of Type 2 Diabetes Irrespective of Weight Gain: The Japan Public Health Center-Based Prospective Study

Objective

The effect of smoking cessation on the risk of diabetes has been reported previously. However, it is unknown whether the association is influenced by weight gain and other potential risk factors.

Methods

The Japan Public Health Center-Based Prospective Study established in 1990 for Cohort I and in 1993 for Cohort II provided data, and 25,875 men and 33,959 women were analyzed. The response rate to the baseline questionnaire was 80.9%, and 68.4% of the respondents participated both the 5- and 10-year follow-up surveys. Smoking cessation was noted during the initial five years and the development of diabetes was reported in the subsequent five years.

Results

An increased risk was observed among individuals who newly quit smoking compared with never smokers among men (odds ratio (OR) = 1.42, 95% CI = 1.03–1.94) and women (OR = 2.84, CI = 1.53–5.29). The risk of developing diabetes among male new quitters who gained 3 kg or more during the 5-year follow-up did not substantially differ from the risk among male never smokers with less than 3 kg of weight gain or no weight gain, while an increased risk was observed among male new quitters with less or no weight gain (OR = 1.46, 95%CI 1.00–2.14). An insignificant increased risk was observed among male new quitters with a family history of diabetes compared with male never smokers with a family history of diabetes. The risk was more than twice as high for male new quitters who used to smoke 25 or more cigarettes per day compared with never smokers (OR = 2.15, 95%CI: 1.34–3.47).

Discussion

An increased risk of diabetes was implied among individuals who quit smoking. However, the increased risk was not implied among those who gained weight over the 5-years of follow-up. Those who had major risk factors for diabetes or who smoked heavier had a higher risk.     

HIV-1 Suppressive Sequences Are Modulated by Rev Transport of Unspliced RNA and Are Required for Efficient HIV-1 Production

The unspliced human immunodeficiency virus type 1 (HIV-1) RNAs are translated as Gag and Gag-Pol polyproteins or packaged as genomes into viral particles. Efficient translation is necessary before the transition to produce infective virions. The viral protein Rev exports all intron-containing viral RNAs; however, it also appears to enhance translation. Cellular microRNAs target cellular and viral mRNAs to silence their translation and enrich them at discrete cytoplasmic loci that overlap with the putative interim site of Gag and the genome. Here, we analyzed how Rev-mediated transport and the splicing status of the mRNA influenced the silencing status imposed by microRNA. Through identification and mutational analysis of the silencing sites in the HIV-1 genome, we elucidated the effect of silencing on virus production. Renilla luciferase mRNA, which contains a let-7 targeting site in its 3′ untranslated region, was mediated when it was transported by Rev and not spliced, but it was either not mediated when it was spliced even in a partial way or it was Rev-independent. The silencing sites in the pol and env-nef regions of the HIV-1 genome, which were repressed in T cells and other cell lines, were Drosha-dependent and could also be modulated by Rev in an unspliced state. Mutant viruses that contained genomic mutations that reflect alterations to show more derepressive effects in the 3′ untranslated region of the Renilla luciferase gene replicated more slowly than wild-type virus. These findings yield insights into the HIV-1 silencing sites that might allow the genome to avoid translational machinery and that might be utilized in coordinating virus production during initial virus replication. However, the function of Rev to modulate the silencing sites of unspliced RNAs would be advantageous for the efficient translation that is required to support protein production prior to viral packaging and particle production.     

Molecular and catalytic properties of 2,4-diacetylphloroglucinol hydrolase (PhlG) from Pseudomonas sp. YGJ3

Gene phlG encoding 2,4-diacetylphloroglucinol hydrolase was cloned from Pseudomonas sp. YGJ3 and expressed in Escherichia coli. Recombinant PhlG was purified homogeneously. It required 2-mercaptoethanol for stability. Km for 2,4-diacetylphloroglucinol and kcat were determined to be 24 μM and 5.8 s(-1) respectively. CoCl2 specifically and significantly activated PhlG.