Acrylamide-Hemoglobin Adduct Levels in a Japanese Population and Comparison with Acrylamide Exposure Assessed by the Duplicated Method or a Food Frequency Questionnaire.

The levels of hemoglobin adducts of acrylamide (AA-Hb), a biomarker of acrylamide exposure, have not been reported for Japanese subjects. Herein, we determined the AA-Hb levels in a Japanese population and compared them with the estimated dietary intake from the duplicate diet method (DM) and a food frequency questionnaire (FFQ). One-day DM samples, FFQ, and blood samples were collected from 89 participants and analyzed for acrylamide. AA-Hb was analyzed using liquid chromatography tandem mass spectrometry and the N-alkyl Edman method. Participants were divided into tertiles of estimated acrylamide intake and geometric means (GMs) of AA-Hb adjusted for sex and smoking status. A stratified analysis according to smoking status was also performed. The average AA-Hb levels for all participants, never, past, and current smokers were 46, 38, 65, and 86 pmol/g Hb, respectively. GMs of AA-Hb levels in all participants were significantly associated with tertiles of estimated acrylamide intake from DM (p for trend = 0.02) and FFQ (p for trend = 0.04), although no association with smokers was observed. AA-Hb levels reflected smoking status, which were similar to values reported in Western populations, and they were associated with estimated dietary intake of acrylamide when adjusted for sex and smoking status.

Dietary exposure to acrylamide in a group of Japanese adults based on 24-hour duplicate diet samples.

Acrylamide is a probable human carcinogen and known human neurotoxin that can be generated in food through heating. Using a mathematical modelling approach, our previous study estimated long-term average dietary exposure to acrylamide in the Japanese people; however, the validity of these estimates remained unknown. Here, we aimed to obtain a more accurate estimate of acrylamide exposure that would reflect the usual practice of heat processing and consumption of foods in the population. We collected duplicate diet samples and dietary records during 24 h from a group of Japanese adults. A total of 110 duplicate diet samples were analysed for acrylamide by LC-MS/MS. Data from individual dietary records were used to examine the association between dietary acrylamide exposure and consumption of selected food groups (e.g., coffee, tea, confectioneries, and vegetables prepared at high temperature [deep-frying, stir-frying, sautéing, and baking]). Of the 110 homogenised diet samples, 108 contained detectable levels of acrylamide. Dietary exposure to acrylamide ranged from 8 to 1582 ng/kg body weight (bw)/day, with the mean value of 215 ng/kg-bw/day and median value of 143 ng/kg-bw/day. This mean value was higher than the value we previously estimated for Japanese adults using a mathematical approach. Multiple linear regression analysis showed log dietary acrylamide exposure was significantly associated with consumption of coffee and vegetables prepared at high temperature during 24-hr of sampling (adj. R2 = 0.250, p < 0.001). We revealed significant difference in dietary acrylamide exposure between participants who had coffee and vegetables prepared at high temperature (median, 169 ng/kg-bw/day; range, 35-1224 ng/kg-bw/day, n = 42) and those who had none of them (median, 75 ng/kg-bw/day; range, 8-311 ng/kg-bw/day, n = 15) (Steel-Dwass test, p < 0.05).

Effect of the classic 1-week glycogen-loading regimen on fat-loading in rats and humans.

The purpose of this study was to elucidate the fat-loading effect of the classic 1-wk glycogen-loading regimen histologically in rats and physiologically in humans. In the rat and human studies, an exhaustive swimming exercise and cycle ergometer exercise were loaded on day 1 of a 6-d feeding period, respectively. Thereafter, both the rats and humans were divided into a glycogen-loading regimen consisting of a 3-d high-fat diet and a 3-d high-carbohydrate diet or a 6-d high-carbohydrate diet. After the feeding period in the human study, the human subjects performed a test exercise on day 7 using a cycle ergometer. In the rat study, the intramuscular triglyceride (IMTG) content was 69% greater (p<0.05) after the glycogen-loading regimen than after the high-carbohydrate diet feeding on day 7. In the human study, the respiratory exchange ratios (RER) after the glycogen-loading regimen were 4.9-6% lower than those after the high-carbohydrate diet during the test exercise on day 7 (p<0.05). Our findings suggest that the classical 1-wk glycogen-loading regimen maintained the storage and enhanced the utilization of energy sources during exercise in the skeletal muscle, and that it provides a fat-loading effect, in addition to the glycogen-loading effect, to the skeletal muscle.

Dosing schedule-dependent change in the disruptive effects of interferon-alpha on the circadian clock function.

Altered homeostatic regulation, including the disturbance of circadian rhythms, is often observed in patients undergoing interferon (IFN) therapy. We reported previously that IFN-alpha has the ability to modulate the circadian clock function at the molecular level and that the alteration of clock function could be overcome by changing the dosing schedule. In this study, we investigated the influence of IFN-alpha on the intrinsic biological rhythms in mice by comparing two dosing schedules, continuous administration and repetitive injection. Continuous administration of IFN-alpha to mice decreased the rhythm amplitude of locomotor activity, body temperature, leukocyte counts, and plasma corticosterone levels. The treatment also suppressed the oscillation in the expression of clock genes in the liver. On the other hand, modulation effects were scarcely observed in mice treated with repetitive injection of IFN-alpha. These results indicate that treatment with IFN-alpha does not always modulate the circadian clock function. This notion was also supported by in vitro findings that the inhibitory action of IFN-alpha on the expression of clock genes was dependent on its exposure time to cells. The alteration of clock function induced by IFN-alpha could be avoided by optimizing the dosing schedule.

BMP2, BMP4, and their receptors are expressed in the differentiating muscle tissues of mouse embryonic tongue.

To investigate the role of bone morphogenetic proteins (BMPs) in the differentiation process of skeletal muscle, we analyzed the in vivo expression of BMP2 and BMP4, of BMP receptors (BMPR) IA, IB, and II, and of activin receptors (ActR) IA, II, and IIB in mouse tongue muscle between embryonic day 11 (E11) and E17. The mRNA expression levels for BMP2 were 5-fold to 11-fold greater than those for BMP4 between E13 and E17 (P < 0.05-0.01). Expression of the BMP2, BMPRIB, ActRIA, ActRII, and ActRIIB proteins was first observed at E13. Expression of BMP2 and BMPRIB was detected in the whole area of the differentiating muscle tissues identified by immunostaining for fast myosin heavy chain (fMHC), but that of ActRIA, ActRII, and ActRIIB was detected only in the peripheral area of the differentiating muscle tissues. In the E15 tongue, all of the BMPs, BMPRs, and ActRs studied herein were expressed in the whole area of the differentiating muscle tissues identified by immunostaining for fMHC. These results suggest that BMPs play a role in the differentiation of tongue muscle tissues at E15 but have little or no effect at E13.

Dietary factors and development of impaired glucose tolerance and diabetes in a general Japanese population: the hisayama study.

BACKGROUND: There have been few prospective studies on diet and glucose abnormalities as determined by oral glucose tolerance test. METHODS: To investigate the impact of dietary factors on the development of glucose intolerance including diabetes and impaired glucose tolerance, we performed a follow-up survey of 1,075 subjects aged 40-74 years of normal glucose tolerance from 1988 through 1993/1994 by repeated 75 g oral glucose tolerance test and dietary survey. Information on habitual food consumption was obtained using a semiquantitative food frequency method. RESULTS: Of the total subjects studied, 119 (11.1%) developed impaired glucose tolerance and 24 (2.2%) developed diabetes during the follow-up. At baseline, the age-adjusted amount of alcohol intake was significantly higher in males who developed glucose intolerance than in those who did not (26.7 g vs. 15.7 g, p < 0.05), while the polyunsaturated/saturated fatty acids (P/S) ratio was significantly higher in females with future glucose intolerance (1.42 vs. 1.31, p < 0.05). Among the female subjects who developed glucose intolerance, the intake of animal fat less decreased during the follow-up period compared with normal subjects, resulting in a significant decrease in the P/S ratio (-0.09 vs. 0.05, p < 0.05). In a multiple logistic regression analysis, alcohol intake at baseline for males and decreased P/S ratio during the follow-up for females remained a significant risk factor for glucose intolerance independent of other dietary and non-dietary factors as well. CONCLUSIONS: These results suggest that a high intake of alcohol and a decreased P/S ratio contribute to the risk of glucose intolerance in contemporary Japanese.

[Changes in nutritional status and nutritional intake among elderly residents of a community over a 10-year period: the Hisayama Study].

The purpose of this study was to investigate the changes in nutritional status and nutrient intake among 387 elderly residents (> or = 60 y.o.) of Hisayama Town. A dietary survey was carried out at baseline in 1988 and repeated at the end of the follow-up period in 1998. During the 10-year follow-up period, mean values of body height and weight, and body mass index significantly decreased in both sexes. Likewise, blood hemoglobin and serum total cholesterol levels significantly decreased, while serum albumin and HDL-cholesterol levels significantly increased. Among dietary factors, mean energy intake significantly decreased due mainly to a decrease in the amount of carbohydrate intake, but no significant changes in the amount of protein and fat intakes were observed. The percentages of the Recommended Dietary Allowance for all nutrients eaten except for iron changed at the levels above 100%. The percentage of energy derived from carbohydrate significantly decreased, while those from protein and fat significantly increased. In conclusion, among community-dwelling healthy elderly people, mean energy intake significantly decreased due to a decrease in the amount of carbohydrate intake, and the fat intake relatively increased, with advancing age, but the blood lipid profile remained unchanged.