Astaxanthin (ASX) is a carotenoid that has potent protective effects on diabetic nephropathy in mice model of type 2 diabetes. In this study, we investigated the protective mechanism of ASX on the progression of diabetic nephropathy using an in vitro model of hyperglycemia, focusing on mesangial cells. Normal human mesangial cells (NHMCs) were cultured in the medium containing normal (5 mM) or high (25 mM) concentrations of D-glucose. Reactive oxygen species (ROS) production, the activation of nuclear transcription factors such as nuclear factor kappa B (NFkappaB) and activator protein-1 (AP-1), and the expression/production of transforming growth factor-beta 1 (TGFbeta(1)) and monocyte chemoattractant protein-1 (MCP-1) were evaluated in the presence or absence of ASX. High glucose (HG) exposure induced significant ROS production in mitochondria of NHMCs, which resulted in the activation of transcription factors, and subsequent expression/production of cytokines that plays an important role in the mesangial expansion, an important event in the pathogenesis of diabetic nephropathy. ASX significantly suppressed HG-induced ROS production, the activation of transcription factors, and cytokine expression/production by NHMCs. In addition, ASX accumulated in the mitochondria of NHMCs and reduced the production of ROS-modified proteins in mitochondria. ASX may prevent the progression of diabetic nephropathy mainly through ROS scavenging effect in mitochondria of mesangial cells and thus is expected to be very useful for the prevention of diabetic nephropathy.

Although the mechanisms have not yet been completely investigated, WBH may provide a new therapeutic or preventive modality against obesity-related diseases such as T2DM and metabolic or insulin resistance syndrome.

Insomnia is one of the most common health problems and has recently been re-termed 'Disorders of initiating and Maintaining Sleep', or DIMS. The main purpose of the present study was to investigate the relationship between daily psychosocial stressors, to which workers are exposed in occupational and/or private life, and insomnia among male industrial workers in a medium-sized company located in Nagasaki City, Japan. All of the workers in the company (n = 368, male = 319) were asked to answer six sleep related questions and 24 questions about working and private conditions. Two hundred and seventy-one (85.0%) of them completed the questionnaire (average age was 40.9 years old). Twenty seven point seven per cent of the subjects complained of insomnia in the last month prior to the survey and the prevalence was in general accord with previous surveys. On the other hand, the proportion of hypnotic use (1.1%), especially in insomniac group (2.7%) was lower than previous reports. The results of multiple logistic regression analysis demonstrated that four psychosocial factors were significantly associated with insomnia: i.e. VDT work overload (odds ratio [OR] 5.058; 95% confidence intervals [95% CI] 2.381-10.745), limited space of bedroom (OR 2.612; 95% CI 1.283-5.683), over-involvement in job (OR 2.78; 95% CI 1.188-6.540), frequent alcohol beverages consumption (OR 2.595; CI 1.77-5.719).

Previously we have demonstrated that whole body hyperthermia (WBH) improves insulin resistance in diabetic mice. The aim of the present study was to perform a gene expression analysis of the liver and adipose tissue of obesity-induced insulin resistant diabetic mice (db/db mice) after WBH and to define the molecules that play the important role in improvement of insulin resistance by WBH. Male db/db mice were treated with WBH 3 times per week for 12 weeks. Total RNA was extracted from the liver and adipose tissue of db/db mice, and differences in the gene expression profiles among db/+ mice, untreated db/db mice, and WBH-treated db/db mice were investigated using a high-density DNA microarray. WBH directly targets liver and adipose tissue, resulting in modifications in NF-kappaB and IL-6 signalling pathways, as well as lipid metabolism. Although the mechanisms have not yet been completely investigated, we can conclude that WBH may provide a new therapeutic or preventive modality against type 2 diabetes mellitus and metabolic or insulin resistance syndrome through the modification of several signalling pathways.

BackgroundMany women become obese during pregnancy and the postpartum period. Weight gain and obesity in the general population are often attributed to abnormalities of autonomic nervous system (ANS) activity. The aim of this study was to clarify change in ANS activity, body weight, percentage fat mass (%FM), and body mass index (BMI) and the factors regulating the return to the pre-pregnancy weight in the first year postpartum.MethodsThis study was conducted from 2012 to 2016 at the University Hospital of the Kyoto Prefectural University of Medicine and a nearby obstetrics and gynecology clinic in Japan. Body weight and %FM were measured in 51 women using a dual-frequency body composition measuring device. Heart rate variability and R–R spectral transformation were used as indicators of ANS activity. All parameters were calculated at three postpartum time points. Repeated measure analysis of variance was used for comparisons between measurement times. A multivariable Cox proportional hazards model was conducted to determine factors associated with the return to pre-pregnancy weight.ResultsMean body weight, %FM, and BMI decreased significantly over time after delivery (P < 0.001, P < 0.001, P < 0.001). However, ANS activity did not differ among subjects in the three time points. 25.5 % of subjects had still not returned to their pre-pregnancy body weight by 150–270 days postpartum, and 19.6 % had not by 270–360 days postpartum. Normal-weight obesity (NWO; BMI of 18.5–25 kg/m2 and %FM of ≥30 %) was observed in several subjects at each measurement. The results of analysis using a multivariable Cox proportional hazards model suggest that ANS activity had no significant correlation with the return to pre-pregnancy weight.ConclusionsThe management of body weight and %FM after delivery is considered important. These findings suggest that ANS activity is not associated with the return to pre-pregnancy weight, albeit that sample size was small.