Effects of high ß-glucan barley on visceral fat obesity in Japanese individuals: A randomized, double-blind study.

OBJECTIVE: The aim of this study was to investigate whether a diet in which high ß-glucan barley was substituted for rice would reduce visceral fat obesity in Japanese individuals. METHODS: A randomized, double-blind, placebo-controlled intervention study was conducted with 100 Japanese individuals with waist circumference (WC) ≥85 cm for men or ≥90 cm for women and body mass index (BMI) ≥24 kg/m2. Participants were randomly assigned to consume a mixture of rice and either high ß-glucan barley (test group, 4.4 g/d) or ß-glucan-free barley (placebo group) for 12 wk. Blood samples and computed tomography scans were obtained before and after the trial. RESULTS: Both groups showed decreases in body weight and BMI, and these changes were significantly greater in the test group. WC and visceral fat area (VFA) significantly decreased in both groups (VFA: -10.7 cm2 in the test group; -6.8 cm2 in the placebo group). These changes did not differ significantly between the groups. However, a subgroup analysis of participants with VFA ≥100 cm2 showed a significant decrease in the test group, and this decrease was significantly greater than in the placebo group. CONCLUSIONS: The intake of high ß-glucan barley led to significant and safe reductions in VFA, body weight, BMI, and WC in individuals with visceral fat obesity with VFA ≥100 cm2. Barley high in ß-glucan may contribute to preventing visceral fat obesity.

Effect of waxy barley, Kirarimochi, consumption on bowel movements of late-stage elderly residents at Roken nursing home.

BACKGROUND: It is very important for the late-stage elderly to have the least stressful bowel movements for maintaining a good quality of life. It is generally accepted that consuming adequate dietary fiber is a promising method for the prevention and management of stressful bowel movements such as those during constipation. Therefore, we examined the effect of long-term consumption of waxy barley, which is high in dietary fiber, on the bowel movements of the late-stage elderly living at Roken nursing home (a geriatric health services facility), Japan. METHODS: We compared the defecation and laxative administration frequencies of the subjects before and after waxy barley consumption, for which we served 28 residents a boiled mixture of rice and waxy barley (variety name, Kirarimochi) as the main meals for 5 months, from November to March. In October, all residents were served boiled rice as the main meals. RESULTS: The residents were categorized into "constipated" subjects and "non-constipated" subjects according to their weekly defecation frequency during October. Among the 14 residents categorized as constipated subjects, monthly number of days with defecation in November, January, and March significantly increased in comparison to monthly number of days with defecation in October. In addition, monthly number of days with laxative administration significantly decreased in December and February in comparison to monthly number of days with laxative administration in October. In contrast, the defecation and laxative administration frequencies did not change after waxy barley consumption among the 14 residents categorized as non-constipated subjects. CONCLUSIONS: Consumption of waxy barley, Kirarimochi, for 5 months improved the bowel movements of the constipated subjects; however, the consumption had no effect on the bowel movements of the non-constipated subjects at Roken nursing home. These results indicate that consuming waxy barley, Kirarimochi, is beneficial for the management of constipation in the late-stage elderly residents at Roken nursing home.

Isolation and characterization of the RAD54 gene from Arabidopsis thaliana.

Homologous recombination (HR) is an essential process in maintaining genome integrity and variability. In eukaryotes, the Rad52 epistasis group proteins are involved in meiotic recombination and/or HR repair. One member of this group, Rad54, belongs to the SWI2/SNF2 family of DNA-stimulated ATPases. Recent studies indicate that Rad54 has important functions in HR, both as a chromatin remodelling factor and as a mediator of the Rad51 nucleoprotein filament. Despite the importance of Rad54 in HR, no study of Rad54 from plants has yet been performed. Here, we cloned the full-length AtRAD54 cDNA sequence; an open reading frame of 910 amino acids encodes a protein with a predicted molecular mass of 101.9 kDa. Western blotting analysis showed that the AtRad54 protein was indeed expressed as a protein of approximately 110 kDa in Arabidopsis. The predicted protein sequence of AtRAD54 contains seven helicase domains, which are conserved in all other Rad54s. Yeast two-hybrid analysis revealed an interaction between Arabidopsis Rad51 and Rad54. AtRAD54 transcripts were found in all tissues examined, with the highest levels of expression in flower buds. Expression of AtRAD54 was induced by gamma-irradiation. A T-DNA insertion mutant of AtRAD54 devoid of full-length AtRAD54 expression was viable and fertile; however, it showed increased sensitivity to gamma-irradiation and the cross-linking reagent cisplatin. In addition, the efficiency of somatic HR in the mutant plants was reduced relative to that in wild-type plants. Our findings point to an important role for Rad54 in HR repair in higher plants.

Molecular cloning and characterization of RAD51-like genes from Arabidopsis thaliana.

Homologous recombination is an essential process for the maintenance and variability of the genome. In eukaryotes, the Rad52 epistasis group proteins serve the main role for meiotic recombination and/or homologous recombinational repair. Rad51-like proteins, such as Rad55 and Rad57 in yeast, play a role in assembly or stabilization of multimeric Rad51 that promotes homologous pairing and strand exchange reactions. We cloned two RAD51-like genes named AtXRCC3 and AtRAD51C from Arabidopsis thaliana. Both AtXRCC3 and AtRAD51C expressed two alternatively spliced transcripts, and AtRAD51C produced two different sizes of isoforms, a long (AtRAD51Calpha) and a short one (AtRAD51Cbeta). The predicted protein sequences of these genes showed characteristic features of the RecA/Rad51 family; especially the amino acids around the ATP-binding motifs were well conserved. The transcripts of AtXRCC3 and AtRAD51C were detected in various tissues, with the highest level of expression in flower buds. Expression of both genes was induced by gamma-ray irradiation. The results of yeast two-hybrid assays suggested that Arabidopsis Rad51 family proteins form a complex, which could participate in meiotic recombination and/or homologous recombinational repair.