Iron deficiency anemia, zinc and vitamin A deficiencies are serious public health problems in Cameroon, as in many developing countries. Local vegetables which are sources of provitamin A carotenoids (PACs) can be used to improve vitamin A intakes. However, traditional meals are often unable to cover zinc and iron needs. The aim of this study was to determine the bioavailability of 3 PACs (α-carotene, β-carotene, and β-cryptoxanthin) in young men, who were fed with a vitamin A-free diet and received iron and zinc supplementation. Twelve healthy participants were divided into three groups and were supplemented with elemental iron (20 mg of iron fumarate), 20 mg of zinc sulfate or iron+zinc (20 mg of iron in the morning and 20 mg of zinc in the evening) for 11 d. They were given a vitamin A- and PAC-free diet from the 6th to the 11th day, followed by a test meal containing 0.55 kg of freshly peeled papaya as a source of PACs. Blood samples were collected four times successively on the 11th day (the test meal day), at T0 (just after the test meal), after 2 h (T2), after 4 h (T4) and after 7 h (T7). Ultracentrifugation was used to isolate serum chylomicrons. Retinol appearance and PAC postprandial concentrations were determined. The supplementation with zinc, iron and iron+zinc influenced the chylomicron appearance of retinol and PACs differently as reflected by retention times and maximum absorption peaks. Iron led to highest retinol levels in the chylomicron. Zinc and iron+zinc supplements were best for optimal intact appearance of α-carotene, β-carotene and β-cryptoxanthin respectively. Supplementation with iron led to the greatest bioavailability of PACs from papaya and its conversion to retinol.
It is thought that both exercise and dietary composition increase the utilization of, and thus the requirement for, certain water-soluble vitamins. However, there have been no studies evaluating the combined impacts of exercise and dietary composition on vitamin utilization. In this experiment, rats were fed a pantothenic acid (PaA)-restricted (0.004 g PaA-Ca/kg diet) diet containing 5% (ordinary amount of dietary fat) or 20% fat (high fat), and were forced to swim until exhaustion every other day for 22 d. PaA status was assessed by urinary excretion, which reflects body stores of water-soluble vitamins. The urinary excretion of PaA in rats fed a 5% fat diet was not affected by swimming (5% fat + non-swimming vs. 5% fat + swim; p>0.05). Excretion of PaA was decreased by the high-fat diet (5% fat + non-swim vs. 20% fat + non-swim; p<0.05) and synergistically decreased by exercise (20% fat + non-swim vs. 20% fat + swim; p<0.05). There was a significant interaction between exercise and a high-fat diet. Plasma PaA concentrations showed changes similar to those seen for urinary excretion. The experiment was then repeated using rats fed a PaA-sufficient (0.016 g PaA-Ca/kg diet) diet, and PaA excretion was again synergistically decreased by the combination of exercise and a high-fat diet (p<0.05). These results suggest that the combination of exercise and a high-fat diet synergistically increases the requirement for PaA.
Hexacosanoic acid (C26:0) (1), a very long-chain fatty acid, is related to various diseases such as adrenoleukodystrophy (ALD), adrenomyeloneuropathy (AMN) and atherosclerosis. As the level of 1 higher than the normal is related to diseases above, hexacosanoic acid (1) and the ceramide 2, which contains 1, are thought to play an important role in various tissues. Hexacosanoic acid (1) is known to be a waxy solid and to be hard to dissolve in water as well as organic solvents. Due to this physical property, it is not easy to handle hexacosanoic acid (1) in a laboratory. Therefore, efficient chemical synthesis of the compounds 1 and 2 has not been reported. Here, we report a versatile synthetic method for hexacosanoic acid (1) and the ceramide 2 containing the fatty acid 1. Synthesis of hexacosanoic acid (1) was achieved by applying the coupling of two alkyl units as a key step. Ceramide 2 was efficiently synthesized by applying the reported procedure together with hexacosanoic acid (1) synthesized here. This synthetic strategy has an advantage of getting various carbon chain length fatty acids and their ceramides by using a variety of carbon chain units. This method is also applicable for large-scale synthesis. In addition, these compounds 1 and 2 are useful for investigation of details of these compounds related to diseases such as ALD and AMN.
This study aimed to explore the mechanism underlying the different effects of diet supplemented with sheep- or duck-meat on serum cytokines of rats. Methods: Male Sprague-Dawley rats were randomly divided into three groups fed on sheep meat, duck meat, or soybean, respectively. The profiles of amino acids and fatty acids of the three diets were examined, and the levels of serum cytokines in rats, including interleukin-1β (IL-1β), IL-2, IL-4, IL-6, IL-10 and tumor necrosis factor-α (TNF-α), were detected 30 d after feeding, using radioimmunoassay. The contents of methionine and glycine in the sheep-meat and duck-meat diets were significantly higher than those in the soybean diet. The content of saturated fatty acids in the sheep-meat diet and duck-meat diet was higher than that in soybeans, while the polyunsaturated fatty acids (PUFAs) in the duck-meat diet were highest and those in the sheep-meat diet were lowest. Serum levels of IL-2 and IL-10 in the rats of the sheep-meat and duck-meat groups were significantly higher than those in the rats of the soybean group (p<0.05). IL-10 and TNF-α in the rats of the sheep-meat group were higher than those in the duck-meat group. But the levels of IL-1β and IL-6 were not significantly different among the three groups. Additionally, there were positive correlations between glycine and IL-1β as well as glycine and IL-2, while negative correlation existed between C18:2 and TNF-α. Methionine, glycine and PUFAs in a diet supplemented with sheep- or duck-meat might influence the levels of serum cytokines in rats, suggesting the potential regulatory mechanism of amino acids and fatty acids from diet in immune responses.
Pyrroloquinoline quinone (PQQ) is a water-soluble quinone compound that has a strong anti-oxidant capacity. A previous study in rats fed a PQQ-depleted diet showed that elevated levels of serum triglyceride (TG) decreased after PQQ supplementation. However, there is only one study reporting the effects of PQQ on serum lipid levels, such as those of TG and cholesterol, in humans. In this study, the effects of PQQ disodium salt (BioPQQTM) on serum TG and cholesterol levels in humans after 6 and 12 wk of treatment at an oral dosage of 20 mg/d were examined. This trial was conducted according to a randomized, placebo-controlled, double-blinded protocol. A total of 29 healthy Japanese adults, ranging from 40 to 57 y old, with normal to moderately high TG levels (110-300 mg/dL) as measured by a recent blood examination, were included in this study. In eleven volunteers out of 29, serum low-density lipoprotein cholesterol (LDL-chol) levels at baseline were high (≥140 mg/dL). After 12 wk, the mean serum TG levels had not changed; however, a marginally significant decrease in the mean LDL-chol (from 136.1 to 127.0 mg/dL) was observed in the PQQ group. In the stratification analysis of the high LDL-chol subgroup (baseline LDL-chol level ≥140 mg/dL), the mean LDL-chol levels decreased significantly from the baseline values in the PQQ group compared to the placebo group. Our study findings suggest that PQQ suppressed the LDL-chol level, which is an important finding, because a high level of this lipid is a risk factor for various lifestyle-related diseases.
Pyrroloquinoline quinone (PQQ) is a coenzyme involved in the redox-cycling system. The supplemental use of PQQ has been examined based on its properties as an antioxidant and redox modulator. Although an animal study on deficiency of PQQ suggested that PQQ contributes to skin conditions, its efficacy in humans has not been reported. The present study aimed to investigate the effects of orally administered PQQ on skin moisture, viscoelasticity, and transepidermal water loss (TEWL) both in dry skin mouse models and in healthy female subjects with a subjective symptom of dry skin. In our dry skin mouse model study, oral intake of PQQ (0.0089%, w/w, in the diet for 6 wk) significantly decreased the number of mast cells in the dermis and the number of CD3+ T-cells in the epidermis. In our human study, oral intake of PQQ (20 mg/d for 8 wk) significantly inhibited the increase in TEWL on the forearm. Finally, subject questionnaires showed positive impressions for the improvement of skin conditions. These results suggest that oral intake of PQQ improves skin conditions both in female subjects with dry skin and in mice with a compromised skin barrier function.
High-fat foods tend to be palatable and can cause addiction in mice via a reinforcing effect. However, mice showed preference for low fat concentrations that do not elicit a reinforcing effect in a two-bottle choice test with water as the alternative. This behavior indicates the possibility that the mechanism underlying fat palatability may differ depending on the dietary fat content. To address this issue, we examined the influences of the opioid system and olfactory and gustatory transductions on the intake and reinforcing effects of various concentrations of a dietary fat emulsion (Intralipid). We found that the intake and reinforcing effects of fat emulsion were reduced by the administration of an opioid receptor antagonist (naltrexone). Furthermore, the action of naltrexone was only observed at higher concentrations of fat emulsion. The intake and the reinforcing effects of fat emulsion were also reduced by olfactory and glossopharyngeal nerve transections (designated ONX and GLX, respectively). In contrast to naltrexone, the effects of ONX and GLX were mainly observed at lower concentrations of fat emulsion. These results imply that the opioid system seems to have a greater role in determining the palatability of high-fat foods unlike the contribution of olfactory and glossopharyngeal nerves.
The aim of this study was to examine the association between regular exercise and dietary intake in Japanese young adults. A cross-sectional study was performed between May 2013 and July 2013 in universities, colleges, and technical schools located in Ibaraki, Kanagawa, Tokyo, and Nara in Japan. The final sample comprised 654 students, 473 females and 181 males, aged 18-24 y. Regular exercise and dietary intake were assessed using validated self-reported questionnaires. Logistic regression analyses were applied to examine the association between regular exercise and dietary intake. A total of 18% females and 40% males spent ≥5 h per week exercising. Females who spent ≥5 h per week exercising were likely to have a higher intake of fruits (odds ratio (OR), 1.84; 95% confidence interval (CI), 1.09-3.13) and a lower intake of cereals (OR, 0.57; 95% CI, 0.33-0.97) than were those who spent <1 h per week. Males who spent ≥5 h per week exercising were more likely to have a higher intake of fish and shellfish (OR, 2.69; 95% CI, 1.07-6.77) than those who spent <1 h per week. In conclusions, young adults who spent ≥5 h per week exercising had a higher intake of fruits among females, and a higher intake of fish and shellfish among males than those who spent <1 h per week. The present findings suggested food group intakes associated with regular exercise in Japanese young adults.
Inflammation has been suggested to play an important role in age-related chronic diseases and disability, and it is associated with nutritional status including obesity and malnutrition. While numerous studies have examined the validity of inflammatory markers in the population studies in Caucasian elderly people, very little information is available for the factors affecting inflammatory markers in Asian elderly people. Among inflammatory markers frequently used for the studies of aging, tumor necrosis factor α (TNF-α) is produced mainly by macrophages, and contributes to production of interleukin-6 (IL-6) and C-reactive protein (CRP), thus directing a chronic inflammatory process in the body. In the present study, we examined the associations between plasma TNF-α level and several factors related to nutrition status, including BMI, albumin, and energy intake in community-dwelling Japanese elderly. We conducted a cross-sectional study of 390 men and women aged 70-86 y (average 73.5 y), who participated in health check-ups. Associations between plasma TNF-α levels, other clinical parameters, and lifestyle factors were analyzed using Spearman’s rank correlation coefficient analysis and multiple linear regression analysis. In elderly men, plasma TNF-α level was positively associated with age, white blood cell count, monocyte count, plasma CRP level, serum creatinine, ureic acid, and triacylglycerol levels, and negatively associated with albumin/globulin ratio, eGFR, and serum HDL-cholesterol level. In elderly women, plasma TNF-α level was positively associated with age, plasma CRP level, and serum triacylglycerol level, and negatively associated with serum albumin and HDL-cholesterol levels. The results of this study suggest that plasma TNF-α is associated with inflammation and insulin resistance in both Japanese elderly men and women, and a prominent association of TNF-α with malnutrition status was observed in elderly women.
The biosynthetic pathways of the thiazole moiety of thiamin were studied in the archaeon Halobacterium salinarum. Thiamin is generated by the union of 4-amino-5-hydroxymethyl-2-methylpyrimidine (pyrimidine) and 5-(2-hydroxyethyl)-4-methylthiazole (thiazole). The biosynthesis of thiazole is different in facultative anaerobes, aerobes and eukaryotes. In eukaryotes, the C-4, -4′, -5, -5′ and -5" of the thiazole is biosynthesized from nicotinamide adenine dinucleotide (NAD), with cysteine as S donor and the C-2 and N atoms of glycine. In facultative anaerobic bacteria, such as Escherichia coli, the precursors of the thiazole are the N and C-2 atoms from tyrosine and C-4, -4′, -5, -5′ and -5" from 1-deoxy-D-xylurose-5-phosphate, again with cysteine as S donor. In aerobic bacteria, such as Bacillus subtilis, L-tyrosine is replaced by glycine. In Archaea, known as the third domain of life, the biosynthetic pathway of thiamin has not yet been elucidated. In the present study in the archaeon H. salinarum, it was shown that both the N and C-2 from glycine are incorporated into the thiazole, rather than the N atom coming from L-tyrosine. These results show that thiazole biosynthesis in H. salinarum more closely resembles the biosynthetic pathway found in eukaryotes.
Oxidative stress reduces cell viability and contributes to disease processes. Flavonoids including anthocyanins and proanthocyanidins reportedly induce intracellular antioxidant defence systems. Thus, in this study, we examined the antioxidant effects of a commercial extract from black soybean seed coats (BE), which are rich in anthocyanin and proanthocyanidin, and investigated the associated intracellular mechanisms in HepG2 cells. HepG2 cells treated with hydrogen peroxide (HPO) showed 60% viability, whereas pretreatment with BE-containing media for 2 h ameliorated HPO-mediated cell death by up to 90%. Pretreatment with BE for 2 h partially blocked HPO-mediated activation of ERK in HepG2 cells, and that for 1 h led to a 20% increase in intracellular total protein phosphatase (PP) activity, which is known to deactivate protein kinases. These results indicate that BE prevents HPO-mediated cell damage by inhibiting ERK signalling, potentially via PPs.
Mental disorders are caused by chronic psychosocial stress, and can cause various symptoms related to the digestive system. We focused on the conjugation of intestinal absorptive and enzymatic mechanisms between chronic social defeat stress (CSDS) model rats and healthy controls to obtain general biochemical data about the intestine of the model in this study. The small intestine was divided into three regions: proximal (PI), middle (MI), and distal (DI); mRNA expression associated with a nutrient absorption, glucose absorption activity, and activities of the digestive enzymes such as maltase, sucrase and lactase was measured. Expression of both sodium-dependent glucose transporter 1 (Sglt1) and glucose transporter 2 gene tended to be higher in the stress group compared to the control group in PI. Glucose absorption was also higher in PI of the CSDS group. Sglt1 and peptide transporter 1 gene expressions in the CSDS group were significantly higher than those in the control group in DI. Furthermore, in PI, expression of the aquaporin 1 gene was significantly higher in the CSDS group compared to the control group. Thus, absorption of some nutrients might be higher in the small intestine of the CSDS rat.