Serum apolipoprotein A-I potentiates the therapeutic efficacy of lysocin E against Staphylococcus aureus.

Lysocin E is a lipopeptide with antibiotic activity against methicillin-resistant Staphylococcus aureus. For unclear reasons, the antibacterial activity of lysocin E in a mouse systemic infection model is higher than expected from in vitro results, and the in vitro activity is enhanced by addition of bovine serum. Here, we confirm that serum from various species, including humans, increases lysocin E antimicrobial activity, and identify apolipoprotein A-I (ApoA-I) as an enhancing factor. ApoA-I increases the antibacterial activity of lysocin E when added in vitro, and the antibiotic displays reduced activity in ApoA-I gene knockout mice. Binding of ApoA-I to lysocin E is enhanced by lipid II, a cell-wall synthesis precursor found in the bacterial membrane. Thus, the antimicrobial activity of lysocin E is potentiated through interactions with host serum proteins and microbial components.

Undernourishment in utero and hepatic steatosis in later life: A potential issue in Japanese people.

Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. The prevalence of NAFLD in Japan has nearly doubled in the last 10-15 years. Increasing evidence supports undernourishment in utero being causatively connected with the risk of NAFLD in later life. Low body mass index (BMI) has been common among Japanese women of childbearing age for several decades due to their strong desire to be thin. It is plausible that insufficient maternal energy intake by pregnant Japanese women may underlie the rapid increase in the prevalence of NAFLD in Japan. In order to clarify the mechanisms by which undernourishment in utero primes adult hepatic steatosis, we developed a mouse model of fetal undernourishment with a hepatic fat deposit-prone phenotype on an obesogenic high fat diet in later life. We found that endoplasmic reticulum (ER) stress response parameters were activated concomitantly with the deterioration of hepatic steatosis and also that the alleviation of ER stress with the chemical chaperone, tauroursodeoxycholic acid (TUDCA), significantly improved hepatic steatosis. Therefore, undernourishment in utero may program the future integration of ER stress in the liver on an obesogenic diet in later life and also induce the deterioration of hepatic steatosis. These results also provide an insight into interventions for the potential high-risk population of NAFLD, such as those born small or exposed to maternal undernourishment during the fetal period, with the alleviation of ER stress by dietary supplements and/or specific food including chaperones.

Prevalence of inappropriate dietary supplement use among pregnant women in Japan.

We investigated the characteristics of dietary supplements and their use by 1,076 Japanese pregnant women, the majority of whom were in mid- to late pregnancy. The subjects completed a self-reported survey on their sociodemographic characteristics, supplement use, and attitudes towards diet. The overall prevalence of supplement use did not change before and after pregnancy (75%); however, daily use increased by approximately twofold with pregnancy (20.2% versus 37.2%). After the onset of pregnancy, supplements containing folic acid were taken for fetal health. Daily users were more likely to be older, have a greater awareness of the risk of neural tube defects (NTD), view supplement use as acceptable, have less diet anxiety, and have more advisers regarding diet. Respondents used supplements containing folic acid alone or with other ingredients. Folic acid intake is recommended to reduce the risk of NTD. However, supplement use began after pregnancy recognition, suggesting a lack of knowledge on the appropriate timing of folic acid use. Information about supplements was obtained mostly from newspapers, magazines, flyers, and stores. These results indicate that more accurate information regarding the optimal timing of folic acid intake and the safety of dietary supplements must be disseminated.

Isocaloric high-protein diet as well as branched-chain amino acids supplemented diet partially alleviates adverse consequences of maternal undernutrition on fetal growth.

Maternal undernutrition causes fetal growth restriction. Protein is a vital dietary nutrient for fetal growth, and branched-chain amino acids (BCAA) are noted to have anabolic actions. In this study, we investigated the effects of maternal high-protein diet or BCAA-supplemented diet upon fetal growth under the condition of maternal calorie restriction. Pregnant mice were calorie-restricted (undernutrition: UN), using either a standard diet (S-UN group), high-protein diet (HP-UN group), or BCAA-supplemented diet (BCAA-UN group) to 70% of the control; dams fed ad libitum with a standard diet (S-NN group) from 10.5days post coitum (dpc) to 18.5dpc. The fetal weights of UN groups were significantly decreased compared to that of S-NN. However, the fetal weights of HP-UN and BCAA-UN were significantly higher by 5% and 4%, respectively, than those of S-UN, concomitant with augmentation of the gene and protein expressions of IGF-I and IGF-II in fetal liver. A high-protein diet as well as BCAA-supplemented diet partially improved fetal growth restriction caused by maternal calorie-restriction, suggesting a pivotal role of them in the amelioration of fetal growth restriction.

Neonatal exposure to leptin augments diet-induced obesity in leptin-deficient Ob/Ob mice.

OBJECTIVE: Epidemiological evidence has revealed that undernutrition in utero is closely associated with obesity and related detrimental metabolic sequelae in adulthood. Recently, using a wild-type (wt) mouse model in which offspring were exposed to intrauterine undernutrition (UN offspring), we reported that the premature leptin surge during neonatal growth promotes lifelong changes in energy regulating circuitry in the hypothalamus, thus playing an important role in the development of pronounced obesity on a high-fat diet (HFD) in adulthood. Here, we further evaluate the essential involvement of leptin in the developmental origins of obesity using leptin-deficient ob/ob mice. METHODS AND PROCEDURES: We assessed the progression of obesity on an HFD in adult leptin-deficient ob/ob male mice that were exposed to intrauterine undernutrition by maternal food restriction (ob/ob UN offspring) or to leptin treatment during the neonatal period; this treatment is comparable to the premature leptin surge observed in the wt-UN offspring. RESULTS: On an HFD, the body weight of the male ob/ob UN offspring paralleled that of the ob/ob offspring exposed to normal intrauterine nutrition (ob/ob NN offspring). In contrast, early exposure to leptin in the ob/ob NN offspring during early neonatal growth reproduced the development of pronounced obesity on an HFD in adulthood. DISCUSSION: The presence of leptin and associated energy regulation are indispensable in the acceleration of obesity on an HFD caused by undernutrition in utero. The premature leptin surge plays an essential role in the developmental origins of obesity as a programming signal during the early neonatal period.

Simultaneous increases of leptin and gonadotropin-releasing hormone following exogenous estrogen administration in women with normally menstrual cycle.

The aim of this study was to investigate whether administration of exogenous estrogen affects the changes of leptin and GnRH levels in women with normal menstrual cycle. A total of 18 women received a bolus intravenous injection of 20 mg conjugated estrogen (premarin group) at 0800 during the fifth day of menstrual cycle, while another 18 women were administered 20 mL of normal saline as the control group. Fasting blood samples were collected at 0, 4, 8, 24, 28, 32, 48, 56, 72 and 96 hours after injection for analyses of leptin, GnRH, estrone (E(1)), estradiol (E(2)), LH and FSH. Both the mean plasma levels of E(1) and E(2) were significantly increased from 4 hours and significantly sustained elevated levels up to 72 hours after injection of premarin. Simultaneous significant increases of leptin and GnRH levels were observed at 28, 32 and 48 hours after injection, while the controls remained constant. The mean LH and FSH levels were initially suppressed and then significantly increased at 56 and 72 hours after premarin administration. Leptin appears to be involved in the regulation of positive feedback mechanism of estrogen by conveyance of metabolic signal to affect the release of GnRH in hypothalamus, while its participation in the modulation of negative feedback remains unknown.