Maternal green tea extract intake during lactation attenuates hepatic lipid accumulation in adult male rats exposed to a continuous high-fat diet from the foetal period.

BACKGROUND: Maternal lipid intake in the early postnatal period has a long-term effect on the possibility of fatty liver formation in children; besides, the importance of lipid consumption during lactation for children's health has been suggested. Green tea extract (GTE) contains abundant catechins, and it has been reported to improve lipid metabolism and prevent fatty liver. OBJECTIVE: The aim of this study was to examine the effects of maternal GTE intake during lactation on hepatic lipid accumulation in adult male rats exposed to a continuous high-fat (HF) diet from the foetal period. METHODS: Pregnant Wistar rats received diets containing 13% (control-fat, CON) or 45% (high-fat, HF) fat. CON-fed mothers received the same diet during lactation, whereas HF-fed mothers received either HF diet alone or HF diet supplemented with 0.24% GTE. At weaning, male offspring were divided into three groups, i.e. CON/CON/CON, HF/HF/HF (HF-offspring) or HF/HF+GTE/HF (GTE-offspring), and were fed until 51 weeks. RESULTS: A significant hepatic triglyceride (Tg) accumulation was observed in the HF-offspring when compared with the other offspring. This is presumed to be caused by the promotion of Tg synthesis derived from exogenous fatty acid due to a significant increase in diacylglycerol O-acyltransferase 1 and a decrease in Tg expenditure caused by decreasing microsomal triglyceride transfer protein (MTTP) and long-chain acyl-CoA dehydrogenase. On the other hand, attenuated hepatic Tg accumulation was observed in the GTE-offspring. The levels of the hepatic lipid metabolism-related enzymes were improved to the same level as the CON-offspring, and particularly, MTTP was significantly increased as compared with the HF-offspring. CONCLUSION: This study indicates the potential protective effects of maternal GTE intake during lactation on HF diet-induced hepatic lipid accumulation in adult male rat offspring and the possible underlying mechanisms.

Long-term effects of maternal resveratrol intake during lactation on cholesterol metabolism in male rat offspring.

Resveratrol (RSV) can protect against non-communicable diseases by improving cholesterol metabolism. However, it is unclear that effects of maternal RSV intake on health of adult offspring. In this study, we examined effects of maternal RSV intake during lactation on cholesterol metabolism in adult male rat offspring. Female Wistar rats were fed a control diet (CON) supplemented with or without RSV (20 mg/kg body weight/day) during their lactation period. Male offspring were weaned onto a standard diet and maintained on this diet for 36 weeks. As a result, plasma cholesterol level significantly decreased in RSV offspring compared to CON offspring. Furthermore, a decrease in hepatic 3-hydroxy-3-methylglutaryl-CoA reductase level and an increase in hepatic LDL-receptor level were observed in the RSV offspring. These results indicate that maternal RSV intake causes long-term decrease in plasma cholesterol level in the offspring through suppression of hepatic cholesterol biosynthesis and promotion of hepatic cholesterol uptake.

Polyphenol-enriched azuki bean (Vina angularis) extract reduces the oxidative stress and prevents DNA oxidation in the hearts of streptozotocin-induced early diabetic rats.

We examined the changes in the heart of rats at the early stages of streptozotocin (STZ)-induced diabetes, and whether azuki bean extract (ABE) could influence these changes. The experimental diabetic rats received 0 or 40 mg/kg of ABE orally for 4 weeks, whereas the control group rats received distilled water. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and expression of proteins associated with peroxisomal FA ß-oxidation as well as oxidative stress markers were examined. The levels of peroxisomal ACOX1 and catalase of the diabetic groups were significantly higher than those in the control group. The levels of p62, phosphorylated-p62 (p-p62) and HO-1 in the STZ group were significantly higher than those in the control group, and the levels of p-p62, HO-1, and 8-OHdG were significantly lower by ABE administration. The STZ-induced early diabetes increases the levels of proteins related to peroxisomal FA ß-oxidation and oxidative stress markers in hearts. ABE protects diabetic hearts from oxidative damage.

Elucidation of the mechanism of changes in the antioxidant function with the aging in the liver of the senescence-accelerated mouse P10 (SAMP10).

Senescence-accelerated mice are known to display a variety of deficits and signs of accelerated aging, but the specific mechanisms involved in this process are still unclear. In this study, we examined the expression levels of antioxidant enzymes, transcription factors responsible for the regulation of expression of these enzymes, and mitochondrial proteins in the liver of SAMP10 and SAMR1 mice at 3 and 12 months of age using western blotting analysis. To investigate the amount of oxidative damage to DNA, levels of 8-OHdG were measured in the liver of these mice. At 3 months of age, the levels of catalase, Mn-SOD, GPx, UQCRC2 and COXIV were significantly upregulated in SAMP10 mice compared with that in SAMR1 mice. However, NDUFS3 levels were not significantly different at this young age. In contrast, the expression level of catalase was significantly lower, and the levels of phosphorylated FoxO-1a and UQCRC2 were significantly higher in SAMP10 mice compared to those in SAMR1 mice; however, at 12 months of age, there were no significant differences in Mn-SOD, GPx, total -FoxO-1a, COXIV, and NDUFS3 expression between the two groups of mice. The levels of 8-OHdG in the liver were markedly higher in 12-month-old SAMP10 mice than those in 3-month-old SAMP10 and SAMR1 mice. These results suggest that an increase in number of mitochondria or a collapse in the balance between the levels of complexes I and III results in an increase in the amount of ROS and induces the expression of antioxidant enzymes in the liver of SAMP10 mice at 3 months of age. Although young SAMP10 mice produce a large amount of ROS, they also produce suitable levels of antioxidant enzymes that decompose ROS; consequently accelerated aging does not occur in young SAMP10 mice. In addition to excessive ROS production which is an important cause of aging, the level of catalase was significantly lower in SAMP10 than that in SAMR1 mice. These results suggested that overexpression of ROS and a decrease in the levels of catalase resulted in the accelerated aging observed in older SAMP10 mice. Moreover, the level of phosphorylated FoxO-1a was increased in SAMP10 compared to that in SAMR1 mice though the total amount of FoxO-1a was not significantly different between the two groups in old age. These results suggest that some impairment in the regulation mechanism of FoxO-1a phosphorylation is responsible for abnormal catalase expression and that a significant decrease in the level of catalase with aging decisively affects the metabolic balance of ROS; thus, ROS that cannot be metabolized contributes to the accelerated aging of SAMP10 mice.

Maternal resveratrol intake during lactation attenuates hepatic triglyceride and fatty acid synthesis in adult male rat offspring.

Resveratrol (3,5,4-trihydroxystilbene) is a natural polyphenolic compound found in grapes and red wine and has been shown to exert protective effects on the liver preventing lipid accumulation induced by a high-fat diet. However, no studies have shown that the nutritional resveratrol intake by the parental generation has modified lipogenesis in an adult offspring. The aim of this study was to investigate whether maternal resveratrol intake during lactation affects lipogenesis in adult male rat offspring, and if it does, what is the molecular mechanistic basis. Six male pups born from mothers given a control diets during lactation (CC group) and six male pups born from mothers given a control diet as well as resveratrol during lactation (CR group) were fed a standard diet until sacrifice at 36 weeks. Adult male offspring from mothers given resveratrol during lactation (CR group) had lower body weight from the fourth week of lactation until adulthood, but no significant change was observed in the relative food intake. Low levels of plasma triacylglycerol were found in the CR group compared to the CC group. Histopathological analysis of the livers of adult male rat offspring revealed lipid accumulation in hepatocytes in the CC group, whereas lipid droplets were rare in the CR group. Hepatic protein levels of AMPK-phosphorylated at ser403, Sirt1, and Nampt in the CR group were upregulated significantly compared to the CC group. These results indicated the maternal resveratrol intake during lactation-induced activation of AMPK through Sirt1 upregulation. In this study, significant upregulation of the levels of precursor of sterol regulatory element binding protein-1c (SREBP-1c) and downregulation of the ratio of active-SREBP-1c/precusor-SREBP-1c were observed in the CR group compared to the CC group. These results suggested that proteolytic processing of SREBP-1c was suppressed by AMPK in the livers of the CR group. It is well known that SREBP-1c regulates the lipogenic pathway by activating genes involved in triglyceride and fatty acid synthesis. The present study showed significant downregulation of hepatic fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) levels in the CR group. These results indicated that maternal resveratrol intake during lactation suppressed SREBP-1c cleavage and nuclear translocation and repressed SREBP-1c target gene expression such as FAS and ACC in the livers of adult male offspring. These changes attenuate hepatic triacylglycerol and fatty acid synthesis in adult male offspring.

The relationship between tooth eruption and ingestion of 15 food items among children aged 18-20 months.

Objectives　If children in formative stages ingest foods that are too hard or too soft, they can experience delays in oral cavity functions. Therefore, it is important for young children to receive foods of appropriate hardness in relation to their chewing ability. We investigated the relationship between the ingestion of 15 different food items and tooth eruption among children aged 18-20 months.Methods　Caregivers from Japanese municipalities who took their children for an 18-month health check-up were given an anonymous questionnaire. Questionnaires were only given to caregivers who provided direct consent and were returned by mail upon completion. The questions inquired about the ingestion of 15 different food items in an attempt to elucidate a correlation between the degree of food hardness that children can chew, tooth eruption, and development of oral functions. A chi-squared test and Fisher's exact test were used to evaluate the relationship between the ingestion of the 15 food items and tooth eruption. The Hokkaido University Human Research Ethics Committee approved this study.Results　Of the 501 caregivers who received the questionnaire, there were 210 responses (40.9%) and 202 (40.3%) of those were used in the analysis. Thirty children (14.9%) had non-eruption of the premolars. Children without absolute eruption of the premolars ate pork and/or beef steak more frequently than those who had their first four premolars.Conclusion　Our results suggest that at least 10% of children at the standard tooth eruption age experience delays in oral cavity maturation. This percentage indicates some children consume hard foods inappropriate for premolar development. We propose that caregivers prepare fresh greens and meat of suitable hardness according to the chewing ability of developing children.