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Nitrogen (N) is a major macronutrient that is essential for plant growth. It is important for us to understand the key genes that are involved in the regulation of N utilization. In this study, we focused on a GARP-type transcription factor known as NSR1/MYR2, which has been reported to be induced under N-deficient conditions. Our results demonstrated that NSR1/MYR2 has a transcriptional repression activity and is specifically expressed in vascular tissues, especially in phloem throughout the plant under daily light-dark cycle regulation. The overexpression of NSR1/MYR2 delays nutrient starvation- and dark-triggered senescence in the mature leaves of excised whole aerial parts of Arabidopsis plants. Furthermore, the expression of asparagine synthetase 1 (ASN1), which plays an important role in N remobilization and reallocation, i.e. N reutilization, in Arabidopsis, is negatively regulated by NSR1/MYR2, since the expressions of NSR1/MYR2 and ASN1 were reciprocally regulated during the light-dark cycle and ASN1 expression was down-regulated in overexpressors of NSR1/MYR2 and up-regulated in T-DNA insertion mutants of NSR1/MYR2. Therefore, the present results suggest that NSR1/MYR2 plays a role in N reutilization as a negative regulator through controlling ASN1 expression.

Objective Constipation negatively affects the quality of life by causing abdominal pain and distention. It is common among women and older individuals and frequently encountered in Japan. Coffee and soda ingestion promote gastrointestinal motility; therefore, both liquids are considered effective for alleviating constipation. While invasive approaches or large-scale equipment, such as magnetic resonance imaging and radiography, are needed to confirm their effect on gastrointestinal motility, bowel sound (BS) assessment can be easily and non-invasively performed using low-cost equipment. Differently to coffee, soda contains carbon dioxide and its ingestion may therefore increase gastrointestinal gas and in turn affect the BS generation process. However, the relationship between gastrointestinal gas and acoustic BS features has not yet been investigated. This study aimed to investigate the effect of increased gastrointestinal gas resulting from soda ingestion on the acoustic BS features extracted using a newly improved BS detection technique. Methods We used BS-based acoustic features, including number of BSs detected/min, BS length, and BS power, extracted via an artificial neural network-based BS detection approach, which was developed in a previous study and here improved. Results BSs detected/min and BS length significantly increased after, compared with before, coffee and soda intake. Furthermore, we found that longer BSs (>128 ms) were more significantly associated with soda (200 mL) intake than with coffee (200 mL) intake. Conclusions BS length and BSs detected/min can sensitively evaluate gastrointestinal motility, and BS length may reflect information on gastrointestinal gas in addition to gastrointestinal motility. Recording of BS-based acoustic features is a non-invasive and convenient means to evaluate the effects of liquid intake on gastrointestinal motility in patients with functional gastrointestinal disorders.

Aims Previous studies reported the anti-diabetic effects of α-lipoic acid (αLA) isomers: racemic-αLA, R-αLA, or S-αLA. Previously, we examined the anti-diabetic effects of αLA administered as a food additive, but were unable to demonstrate the differences among different isomers. In this study, αLAs were complexed with γ-cyclodextrin (γCD) for the stability. We then investigated the anti-diabetic effects of racemic-, R-, and S-αLA/γCDs in KKA y mice. Main methods Male type 2 diabetic KKA y mice were divided into 5 groups, and fed either a high-fat-diet (HFD), HFD supplemented with γCD, or HFD supplemented with racemic-αLA/γCD, R-αLA/γCD, or S-αLA/γCD for 4 weeks. At the end of the feeding period, HbA1c and adiponectin levels were measured, PPARγ2 mRNA expression levels were assessed in adipose tissues using real-time PCR, and AMP-activated protein kinase (AMPK) phosphorylation levels were evaluated in the liver by Western blotting. Key findings The anti-diabetic effects of αLA; the isomeric compounds racemic-, R-, and S-αLA/γCD were investigated using a male type 2 diabetic KKA y mouse model. Significant differences were observed in HbA1c and plasma adiponectin levels between R-αLA/γCD-treated mice and control mice. PPARγ2 mRNA expression levels were slightly higher in racemic- and R-αLA/γCD-treated mice. Moreover, AMPK phosphorylation levels were elevated in racemic-αLA/γCD- and R-αLA/γCD-treated mice, but remained unchanged in S-αLA/γCD-treated mice. Significance These results suggested that the stereoisomerism mediates a difference in the anti-diabetic effects of racemic-, R-, and S-αLA/γCDs. Furthermore, the anti-diabetic mechanism of αLA/γCD action may be attributed to the activation of AMPK in the liver.