Obese individuals are considered to have lower energy expenditure (EE) rates than non-obese individuals. We aimed to investigate the effects of various factors related to food intake on diet-induced thermogenesis (DIT) in the EE of obese individuals. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we reviewed relevant literature from PubMed, Embase, and Medline databases from study inception till the end of July 2019. Studies on dietary factors affecting DIT in obese individuals were included. Fifteen studies were included; these studies assessed macronutrient, single-nutrient, or supplement meal compositions, as well as dietary patterns and behaviors. The effect of obesity on DIT was not constant in each study. Differences in DIT pertained to the protein ratio being higher than the fat ratio or the carbohydrate ratio being higher than the fat ratio. High intake of calcium and vitamin D as well as high-oleic peanut supplements increased DIT in obese people. In addition, ascorbic acid intake, fatty acid saturation, and the chain length of various fatty acids had no effects on DIT. In conclusion, the findings suggest that in obese individuals, DIT is associated with various factors related to meal, nutrient, and dietary habits. However, because of the complexity of the relationship between DIT and obesity, it is difficult to determine the critical element underlying this association.
In this paper, a chemiluminescence (CL) method is proposed for retinol determination by combining flow injection (FI) methodology. The CL reaction is based on the oxidation of luminol by diperiodatoargentate(III) (DPA) in the presence of retinol. Under the optimum conditions, the relative CL intensity was linear to the concentration of retinol over the range 5.0×10−3-14 mg L−1 (y=347.26x+2.5944, R2=0.9999, n=8) with limit of detection (LOD) of 1.5×10−3 mg L−1 (S/N=3) and limit of quantification (LOQ) of 5.0×10−3 mg L−1 (S/N=10). The relative standard deviation (RSD) was from 1.04-3.4% over the range studied and injection throughputs of 150 h−1. The method was satisfactorily applied to retinol in pharmaceutical formulation samples. The samples were saponified and extracted with liquid-liquid extraction using ether as an extractant. The possible CL mechanism is supported by CL and UV-visible spectrophotometric studies.
Using rats, we previously found that vitamin C deficiency increases serum levels of interleukin-6 (IL-6) and glucocorticoid, and changes the gene expression of acute phase proteins (APP) in the liver. However, it remains unclear how vitamin C deficiency causes these inflammation-like responses. In this study, we investigated the possibility that changes in gut microbiota are involved in the induction of APP gene expression by vitamin C deficiency. ODS rats that cannot genetically synthesize vitamin C were divided into 4 groups based on the presence or absence of vitamin C or antibiotics and were raised for 15 d. Neomycin, vancomycin, and ampicillin were used as antibiotics, and 300 mg L-ascorbic acid/kg was added to the AIN93G diet. Vitamin C deficiency affected neither the wet tissue weights nor relative abundance of bacteria in the cecal contents. Antibiotic administration increased wet weights of the cecum, cecal contents, and colon, changed the relative abundance of some bacteria in the cecal contents, and decreased serum IL-6 level. However, antibiotic administration had no effect on serum concentrations of corticosterone and α1-acid glycoprotein (AGP), vitamin C concentration in the liver, and mRNA levels of haptoglobin and AGP in the liver. Therefore, disturbance of gut microbiota did not attenuate the increase in glucocorticoid level and induction of APP gene expression due to vitamin C deficiency. This suggests that gut microbiota is not involved in the inflammation-like responses caused by vitamin C deficiency.
To evaluate the effect of iron-fortified formula with different concentrations of bovine lactoferrin (bLF) on improvement of anemic status in term infants who were previously breast-fed. A randomized, controlled, open, and post-market intervention study. A total of 108 infants aged 6-9 mo who were previously breast-fed and weaned were selected. The subjects were divided into three groups with the sequence of outpatient: fortified group 1 (FG1) with a bLF concentration of 38 mg/100 g, FG2 with 76 mg/100 g bLF, FG0 with no bLF. The intervention duration was 3 mo. Weight, height, head circumference and the concentration of hemoglobin (Hb), serum ferritin (SF), serum transferring receptor (sTfR) were measured and sTfR-SF index (TFR-F index) and total body iron content (TBIC) were computed before and after intervention. The primary outcome measures were obtained from 96 infants (35, 33 and 28 for FG0, FG1 and FG2, respectively). After 1 mo of intervention, the changes of Hb level showed no significant difference (p>0.05) among the three groups, however, the Hb level of infants in FG2 were significantly higher than those of infants in the other two groups after 3 mo of intervention (p<0.05). The present data indicated that the formula fortified with 76 mg/100 g bLF positively affected the Hb of anemic infants who were previously breastfed when compared with fortification with 38 mg/100 g bLF and no bLF fortification.
Anemia is a risk factor for frailty. Although various factors can reduce the risk of anemia, information on dietary contributions is limited. This study aimed to evaluate the association between anemia and eating patterns in Japanese elderly. Our study included 6,864 elderly individuals, aged ≥65 y, whose data were obtained from the 2010-2015 National Health and Nutritional Survey, Japan. Anemia was defined as whole blood hemoglobin concentrations <13 g/dL in men, and <12 g/dL in women. We classified eating patterns into 33 food groups, using food items obtained from dietary records, and identified three dietary patterns using principal component analysis method. Participants were assigned and divided into quartiles according to pattern-specific factor scores. We calculated adjusted odds ratios (ORs) for anemia using multivariate logistic regression, and assigned the first quartile (minimum) as the reference. The overall prevalence of anemia was 17.1%. The meats and vegetables eating pattern was characterized by red meat and other vegetables, the Japanese eating pattern by rice and salted or pickled vegetables, and the fruits and vegetables eating pattern by fruits and green-yellow vegetables. Participants in the highest meats and vegetables eating pattern quartile had a 20% lower risk of anemia than those in the lowest quartile (OR 0.81; 95% confidence interval (CI) 0.66-1.00); the Japanese eating pattern participants had a 20% higher risk of anemia (OR 1.28; 95% CI 1.06-1.53). The fruits and vegetables eating pattern participants had no significant change in their risk of anemia. This study may indicate that consuming a high red meat diet prevents anemia in elderly Japanese individuals.
Mouse myoblast C2C12 cells are commonly used as a model system for investigating the metabolic regulation of skeletal muscle. As it is therefore important to understand the metabolic features of C2C12 cells, we examined the effect of glucose starvation on autophagy in C2C12 myotubes. After culture of C2C12 myotubes with high (HG, 25.0 mM) or low (LG, 5.6 mM) glucose concentrations, the concentration of glucose in the LG group had decreased to 0 mM after 24 h of culture and was around 17 mM after 48 h of culture in the HG group. The concentration of lactate increased from 0 to approximately 9 mM at 24 h and then dropped slightly in the LG group, while it increased linearly to 21 mM in the HG group at 48 h. The phosphorylation of p70 S6 kinase, marker for the protein translation initiation was significantly lower and the ratio of LC3-II/LC3-I, marker for the induction of autophagy was significantly higher in the LG group. GLUT1 and hexokinase II expression were significantly higher in the LG group. Together, these changes in glucose and lactate concentrations in the culture media suggest that C2C12 myotubes depend on anaerobic glycolysis. Our findings also suggest that glucose depletion stimulates the expression of key molecules involved in glycolysis and that cellular autophagy is also activated in C2C12 myotubes.
We examined the prevention effect of red clover (Trifolium pratense L.) sprout on metabolic syndrome using a high-carbohydrate and high-fat diet (Western diet; WD)-induced male C57BL/6J obese model mouse. Red clover sprout-lyophilized powder (RC) contained 3.5 mg/g dry-weight of formononetin as a major phenolic compound, as analyzed by high performance liquid chromatography. Supplementation of 0.3% (w/w) RC in a WD (WD+RC) showed an anti-obesity effect and ameliorated lipid metabolism in the obese model mice. Additionally, fasting plasma glucose levels were significantly reduced in the WD+RC group. Administration of 0.1 mg/kg formononetin reduced the postprandial blood glucose level, as assessed using the oral maltose tolerance test. However, no significant formononetin intake effect was observed on the plasma insulin level. These results suggest that the formononetin contained in red clover sprout inhibits α-glucosidase and thereby contributes to reducing the postprandial blood glucose response in mice.
The indicator amino acid oxidation (IAAO) method is a novel method for determining protein requirements. Recently, the protein requirement of healthy young men was reevaluated using this method, and the currently recommended protein requirement based on nitrogen balance study was found to be deficient. Similarly, with respect to experimental animals, the protein concentration used widely in the experimental diets was assumed to be deficient. However, only a few studies have tested the IAAO method in experimental animals. In particular, there are no studies on the protein requirement of adult rats measured using this method. Therefore, we applied the IAAO method to adult rats, to determine their casein protein requirement. Male Wistar/ST rats (15-18 wk old, housed in lighting (lights on from 23:00 to 11:00) conditions) were provided with the test diet including graded casein (5, 7, 9, 13, 17, 21 and 25%) every 2 h from 11:00 to 17:00. Tracer administration of 13C-phenylalanine was performed hourly from 14:00 to 17:00. Breath 13CO2 was measured every 30 min after the first tracer administration. There were significant differences between the 13CO2 concentration of the 5% and 17% casein groups at 17:00 and 18:00 (p<0.05). The mean casein protein requirement and recommended dietary allowance (RDA) were estimated to be 5.2 g/kg BW/d and 7.0 g/kg BW/d using the mixed-effect change point regression model, respectively. Our results indicated that the recommended casein value may be slightly deficient to satisfy the protein metabolic demand of some adult rats.
A treatment for hyperphosphatemia would be expected to reduce mortality rates for CKD and dialysis patients. Although rodent studies have suggested sodium-dependent phosphate transporter type IIb (NaPi-IIb) as a potential target for hyperphosphatemia, NaPi-IIb selective inhibitors failed to achieve efficacy in human clinical trials. In this study, we analyzed phosphate metabolism in rats, dogs, and monkeys to confirm the species differences. Factors related to phosphate metabolism were measured and intestinal phosphate absorption rate was calculated from fecal excretion in each species. Phosphate uptake by intestinal brush border membrane vesicles (BBMV) and the mRNA expression of NaPi-IIb, PiT-1, and PiT-2 were analyzed. In addition, alkaline phosphatase (ALP) activity was evaluated. The intestinal phosphate absorption rate, including phosphate uptake by BBMV and NaPi-IIb expression, was the highest in dogs. Notably, urinary phosphate excretion was the lowest in monkeys, and their intestinal phosphate absorption rate was by far the lowest. Dogs and rats showed positive correlations between Vmax/Km of phosphate uptake in BBMV and NaPi-IIb expression. Although phosphate uptake was observed in the BBMV of monkeys, NaPi-IIb expression was not detected and ALP activity was low. This study revealed significant species differences in intestinal phosphate absorption. NaPi-IIb contributes to intestinal phosphate uptake in rats and dogs. However, in monkeys, phosphate is poorly absorbed due to the slight degradation of organic phosphate in the intestine.
To provide reliable data for high quality epidemiological studies examining the relationship between health and antioxidant intake from daily foods, 107 plant-derived food items (12 rice, bread and noodles, 5 potatoes and starches, 9 pulses, 6 nuts/seeds, 29 vegetables, 22 fruits, 5 mushrooms, 7 algae, and 12 beverages) were selected as commonly consumed foods in Japan based on dietary records, and their antioxidant capacities were evaluated by validated hydrophilic- and lipophilic-oxygen radical absorbance capacity (H-ORAC and L-ORAC) methods. The food items covered more than 60% of total food intake for each category on a weight basis. The H-ORAC and L-ORAC values were widely distributed at 0-210 and 0-30 μmol-Trolox equivalent/g, respectively. The foods possessing potent antioxidant capacities were found in vegetables and fruits as well as other plant-derived foods. In most foods measured, the H-ORAC values were much larger than the L-ORAC values, except for certain kinds of pulses, nuts/seeds, mushrooms, and algae. The ORAC data shown here is sufficient to accurately estimate the antioxidant intake from plant-derived foods in Japan, and should be useful in future epidemiological studies aiming to clarify the biological significance of ORAC values.
Abdominal aortic aneurysm (AAA) is a vascular disease characterized by weakening of vascular walls and progressive dilation of the abdominal aorta. Nicotine, the main component of tobacco, is reportedly associated with the development and rupture of AAA. It is desirable to attenuate the destructive effect of nicotine on vascular walls, using dietary food components. However, effective methods for preventing AAA progression using dietary food components remain unestablished. This study focuses on proanthocyanidins, well known for their potent antioxidant activity. We speculated that proanthocyanidins can suppress nicotine-induced weakening of vascular walls. To estimate the effect of black soybean seed coat extract (BSSCE), rich in proanthocyanidins, on nicotine-induced weakening of the aortic wall, mice were divided into four groups: the control diet and distilled water group (named C), BSSCE solution diet and distilled water group (named B), control diet and 0.5 mg/mL nicotine solution group (named CN), and BSSCE solution diet and 0.5 mg/mL nicotine solution group (named BN). Nicotine-induced degradation of elastin and collagen fibers were significantly suppressed in BN group. The positive areas for matrix metalloproteinase (MMP)-2 and oxidative stress in BN group were significantly decreased compared to those in CN group. These results suggest that proanthocyanidins-rich BSSCE can prevent the weakening of the aortic wall via inhibiting MMP-2 upregulation.
Biotin is a water-soluble B-complex vitamin that functions as a cofactor of five carboxylases. Because biotin-dependent carboxylases catalyze indispensable cellular metabolic functions, biotin deficiency is considered to be involved in various pathological conditions. Moreover, biotin supplementation shows pharmacological effects in vivo. However, the precise mechanisms by which biotin deficiency induces pathological conditions remain unclear. Although abnormal metabolites are used as indicators for biotin deficiency, few comprehensive analyses of total metabolites have been reported. In this study, we analyzed the metabolomic profiles of liver extracts prepared from biotin-sufficient (BS) and -deficient (BD) mice. Thirteen of 126 metabolites showed significantly different concentrations between liver extracts from BD and BS mice. The concentrations of 5 essential amino acids, Met, Val, Thr, Ile, and Leu, and 2 conditionally essential amino acids, Cys and Tyr were significantly lower in BD mice than in BS mice. Among these, the concentrations of sulfur-containing amino acids, Cys and Met, were more than 1.5-fold lower in BD mice. The concentrations of Met metabolites, such as S-adenosylmethionine and S-adenosylhomocysteine were not significantly different between the two groups. The concentrations of glutathione and its reaction intermediates γ-Glu-Cys tendency to be lower in BD mice. The present study revealed that biotin deficiency induces an abnormal amino acids composition, especially among sulfur-containing amino acids and provide important information on the effect of biotin as a pharmacological agent.
Nutrition and light-dark cycle influence rat testicular development. With 9% casein diet (low protein diet) under normal 12 h-12 h lighting cycles (9P), juvenile rat testes undergo normal growth. On the other hand, a low protein diet with constant darkness (D9P) results in a growth arrest of rat testes. Supplementation of cystine to the low protein diet under constant darkness (D9PC) had a tendency to increase testes weight, suggesting an improvement in growth suppression. Whether the growth suppression of testes in D9P is associated with suppression of spermatogenesis has not yet been shown. We aimed to determine the effect of a low protein diet and constant darkness with or without dietary cystine in testes using a histological technique. In the histological assessment, D9P testes showed a decreased number of seminiferous tubules with elongated spermatids, indicating a functional testicular defect in this group. However, cystine supplementation resulted in enhanced spermatogenesis versus control animals (D9PC vs. D9P) implying the importance of cystine to testicular development in this condition. Furthermore, serum testosterone concentration was increased in D9PC suggesting contribution of testosterone to ameliorate spermatogenesis. From these results, we conclude that cystine supplementation to a low protein diet under constant darkness promoted an increase in testosterone which in turn benefitted spermatogenesis.