Childhood obesity has become a public health concern. As the importance of vitamin A (VA) in the body has become increasingly acknowledged, there is limited clinical trial evidence to substantiate the association between VA and childhood obesity. Vitamin A deficiency (VAD) increases the risk of childhood obesity, a finding consistently reported in pregnant women. VA could regulate the adipogenic process, inflammation, oxidative stress and metabolism-related gene expression in mature adipocytes. VAD disrupts the balance of obesity-related metabolism, thus affecting lipid metabolism and insulin regulation. Conversely, VA supplementation has a major impact on efficacy in obesity, and obese individuals typically have a lower VA status than normal-weight individuals. Several studies have attempted to identify the genetic and molecular mechanisms underlying the association between VA and obesity. In this review, we summarize and discuss recent new developments focusing on retinol, retinoic acid, and RBP4 and elucidate and provide an overview of the complex interrelationships between these critical components of VA and childhood obesity. However, the causal relationship between VA status and childhood obesity remains unclear. It is also unknown whether VA supplementation improves the overall obesogenic metabolic profile.

The gastrointestinal (GI) tract is a series of hollow organs that play roles in food digestion and nutrient absorption. To perform these functions, they should recognize the luminal environment and elicit adequate physiological responses, including digestive juice secretion, peristaltic movements, etc. The Ussing chamber technique is an electrophysiological method for measuring transepithelial ion transport and permeability as short-circuit current (I_sc) and transepithelial electrical tissue conductance (G_t) or resistance (TEER), respectively, in vitro. This technique can be applied for the measurement of luminal nutrient sensing and absorption. This article introduces practical methods for measuring luminal nutrient sensing and absorption using intestinal mucosa specimens isolated from humans and experimental animals.

Recent studies have described that vitamin D deficiency/insufficiency is associated with hypertension, insulin resistance, and dyslipidemia, which are major components of metabolic syndrome causing atherosclerosis. Therefore, we investigated the relationship between serum 25-hydroxyvitamin D [25(OH)D] concentration and atherosclerotic disease risk factors in healthy Japanese adults. In the present cross-sectional study, 1,177 subjects (348 males and 829 females) aged 20–72 y living in Japan (34.7–35.0ºN) were evaluated for vitamin D status by measuring serum 25(OH)D concentration. Atherosclerotic disease risk factors were defined as the presence of two or more of the following three risk factors: high blood pressure, dyslipidemia, and hyperglycemia. The percentages of vitamin D deficient and insufficient subjects were 33% and 46% in males and 59% and 32% in females, respectively. Subjects with atherosclerotic disease risk factors were significantly older and had higher BMI than those without it in both sexes. Male subjects with atherosclerotic disease risk factors had significantly lower physical activity and serum 25(OH)D concentration than those without it. In a logistic regression analysis adjusted for confounding factors, serum 25(OH)D concentration showed a significant inverse association with risk factors of atherosclerotic disease in males (OR=0.951, 95%CI: 0.906–0.998), but not in females. A covariance structure analysis also suggested that serum 25(OH)D level has a direct association with risk factors of atherosclerotic disease. In conclusion, we have demonstrated that low serum 25(OH)D level is a significant factor for increased atherosclerotic disease risk factors in males.

Nicotinamide adenine dinucleotide (NAD⁺) is a coenzyme that mediates many redox reactions in energy metabolism. NAD⁺ is also a substrate for ADP-ribosylation and deacetylation by poly (ADP-ribose) polymerase and sirtuin, respectively. Nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1) is a NAD⁺ biosynthesizing enzyme found in the nucleus. Recent research has shown that the maintaining NAD⁺ levels is critical for sustaining muscle functions both in physiological and pathological conditions. However, the role of Nmnat1 in skeletal muscle remains unexplored. In this study, we generated skeletal muscle-specific Nmnat1 knockout (M-Nmnat1 KO) mice and investigated its role in skeletal muscle. We found that NAD⁺ levels were significantly lower in the skeletal muscle of M-Nmnat1 KO mice than in control mice. M-Nmnat1 KO mice, in contrast, had similar body weight and normal muscle histology. Furthermore, the distribution of muscle fiber size and gene expressions of muscle fiber type gene expression were comparable in M-Nmnat1 KO and control mice. Finally, we investigated the role of Nmnat1 in muscle regeneration using cardiotoxin-induced muscle injury model, but muscle regeneration appeared almost normal in M-Nmnat1 KO mice. These findings imply that Nmnat1 has a redundancy in the pathophysiology of skeletal muscle.

The increasing requirement for energy and nutrients as a child grows older may result in nutritional deficiencies. The research was to assess the intake level of essential amino acids in the daily diet of children and adolescents living in rural areas. The research was conducted using a questionnaire that analysed food products consumed every day. The questionnaires were completed with the help of the researcher over a period of 7 d. Anthropometric measurements were carried out on every research participant. The participants’ financial situation was calculated using a 5-degree scale, where 5 meant very good and 1 very bad. Insufficient body mass was recorded in the study group in 11.1% of boys and 14.7% of girls. Excessive body mass occurred more often among the girls (31%) than the boys (27.9%). Among boys aged 7–15 y old, protein provided 12.8% of the calorie requirement, while for the girls the figure was 13.6%. Among pupils aged 16–18 y old, the figures were 14.06% for boys and 14.33% for girls. Analysis of the results showed that irrespective of age or gender, no insufficient intake of amino acids was recorded among the study participants. In the study group of children and adolescents from rural areas, every third study participant suffered from excess body weight. Due to the fact that the intake of essential amino acids exceeded recommended RDA, it is vital that educational programmes are implemented on how to maintain a correctly balanced diet.

The Japanese diet has attracted attention as a factor contributing to the Japanese population’s longevity. A typical Japanese meal, traditionally called “ichiju-sansai,” is composed of various dishes. This study assessed the nutritional adequacy of the Japanese diet using the number of dishes in all meals (NDAM) compared to existing dietary diversity indices (DDIs). This cross-sectional study used data from the 2012 National Health and Nutrition Survey. A total of 25,976 participants aged ≥20 y were included in this study. NDAM was calculated for whole dishes or single foods (except supplements and beverages) from one-day weighted dietary records. The food variety score (FVS), number of foods, dietary diversity score (DDS), and number of food groups are some of the existing DDIs. NDAM had relatively high positive correlation coefficients with potassium, magnesium, and dietary fiber. The partial correlation coefficients with an indicator of the overall nutrient adequacy of NDAM was 0.42 for men and 0.42 for women. It was almost the same as that of the FVS (men: 0.44, women: 0.42) and DDS (men: 0.44, women: 0.43). On the other hand, NDAM, similar to existing DDIs, was also positively correlated with nutrient restriction in both sexes. These findings indicate that the nutrient adequacy of NDAM is similar to that of the existing DDIs. Because of the higher sodium intake and cholesterol intake in higher NDAM and existing DDIs, the effect of higher NDAM on health outcomes must be investigated in future studies.

The present paper first proposes a method for ensuring the safety of commercial herbal supplements, termed the suggested daily intake-based safety evaluation (SDI-based safety evaluation). This new method was inspired as a backward analog of the acceptable daily intake (ADI) derivation from the no observed adverse effect level (NOAEL), the basis of food additive risk analysis; namely, rats are dosed with individual herbal supplement products at the SDI for human use multiplied by 100 (the usual uncertainty factor value) per body weight for 8 d. The primary endpoint is the sign of adverse effects on liver, especially gene expression of cytochrome P450 (CYP) isoforms. The proposed method was then applied to three butterbur (Petasites hybridus) products without pyrrolizidine alkaloids but lacking clear safety information. Results showed that two oily products markedly enhanced the mRNA expression of CYP2B (>10-fold) and moderately enhanced that of CYP3A1 (<4-fold) with liver enlargement. These products also caused the renal accumulation of alpha 2-microglobulin. One powdery product showed no significant effect on liver and kidney. The large difference in effects of products was due to the difference in chemical composition revealed by liquid chromatography–mass spectroscopy. The oily and the powdery products required attention in terms of safety and effectiveness, respectively. Finally, the results from the SDI-based safety evaluation of butterbur and other herbal supplement products were grouped into four categories and cautionary notes were discussed. The SDI-based safety evaluation of their products by herbal supplement operators would contribute to safe and secure use by consumers.

A natural sugar alcohol, D-pinitol, has been reported to be a potential compound for osteoporosis treatment via inhibiting osteoclastgenesis. However, research on the effects of pinitol on osteoporosis in vivo is still limited. The present study investigated the protective effects of pinitol on ovariectomized mice and attempted to elucidate this mechanism in vivo. Four-week-old female ovariectomized ICR mice were employed as a postmenopausal osteoporosis model and treated with pinitol or estradiol (E2) for 7 wk. Thereafter, serum calcium content, phosphorus content, tartrate-resistant acid phosphatase (TRAcP) and bone-specific alkaline phosphatase activity (BALP) were measured. Bilateral femurs were isolated, and bone marrow protein was collected through centrifuge. Dry femurs were weighed, while femur length, cellular bones, and bone mineral content were measured. D-chiro-Inositol (DCI) and myo-inositol (MI) content in serum and bone marrow was measured by GC-MS. At the end of experiment, the serum BALP and TRAcP activities of the OVX mice were suppressed significantly by treatment with either pinitol or E2. Femur weight, cellular bone rate, Ca and P content were improved by pinitol or E2. The DCI content of the serum of OVX decreased significantly, although it recovered to some extent after pinitol treatment. Pinitol significantly increased the ratio of DCI to MI in serum or bone marrow protein in the observed OVX mice. Besides, pinitol had no significant effects on osteoblast viability and differentiation. The present results showed that continuous pinitol intake exerts potent anti-osteoporosis activity via elevating DCI content in serum and bone marrow in OVX mice.