Nutrition Research and Practice最新文献

Background/objectives: Quercetin (QT) is a plant flavonoid that offers health benefits owing to its various bioactive properties; however, as a hydrophobic substance, it has considerably low bioavailability. We previously demonstrated that QT nanoemulsion (QT+NE) formulated via oil-in-water nanoemulsification exhibited more effective cholesterol-lowering activity than ordinary QT in high cholesterol-fed rats. In this study, we investigated the effects of QT+NE on the regulation of skeletal muscle mitochondrial function in high-fat diet (HD)-fed mice.

Materials/methods: C57BL/6J mice were fed a normal chow diet (ND), HD (45% of calories from fat), or HD with 0.05% QT+NE or QT for 11 weeks. We analyzed sirtuin 1 (SIRT1) activation, mitochondrial changes, and the expression of genes involved in mitochondrial biogenesis in skeletal muscle.

Results: Body weight and body weight gain decreased in the QT+NE group compared with that in the HD group (P < 0.05), but not in the QT group. Epididymal adipose tissue weight decreased in both the QT and QT+NE groups (P < 0.05). Plasma lipid levels also improved in both the QT and QT+NE groups (P < 0.05). QT+NE intake upregulated the messenger RNA levels of SIRT1, peroxisome proliferator-activated receptor-γ coactivator 1-α, nuclear respiratory factor 1, and mitochondrial transcription factor A in skeletal muscle compared with HD intake alone (P < 0.05), whereas QT did not. In particular, SIRT1 activity was significantly increased in the QT+NE group compared with that in the QT group (P < 0.05). HD intake reduced mitochondrial DNA content compared with ND intake; nevertheless, QT+NE intake retained it (P < 0.05).

Conclusion: Collectively, our findings suggest that QT+NE may be beneficial in enhancing mitochondrial biogenesis in skeletal muscle of HD-fed mice, which may be associated with SIRT1 activation.

Background/objectives: Sleep duration and diet quality are reportedly associated with the risk of diabetes. This study aimed to examine the risk of diabetes according to sleep duration and diet quality in middle-aged Koreans.

Subjects/methods: Using the Korea National Health and Nutrition Examination Survey 2019-2020, raw data from 2,934 participants aged 40-64 yrs (1,090 men and 1,844 women) who were not diagnosed with type 2 diabetes were analyzed. With a sleep duration of 7-7.9 h per night as the referent category, diet quality was assessed using the Korean Healthy Eating Index (KHEI), which comprises adequacy, moderation, and energy balance.

Results: The study results showed that individuals with a short sleep duration had significantly higher blood glucose (P = 0.034) and HbA1c levels (P < 0.001) than those had by individuals with a sleep duration of 7-7.9 h. Within the group with a sleep duration of 7-7.9 h, the lowest quintile of the KHEI score had a significantly higher risk of prediabetes than that had by the highest quintile of the KHEI score (Model 1: odds ratio [OR], 1.775; 95% confidence interval [CI], 1.072-2.939; P < 0.05 and Model 2: OR, 1.731; 95% CI, 1.040-2.882; P < 0.05).

Conclusion: Our findings suggest that achieving the sleep duration of 7-7.9 h and eating good diet are associated with the lowest risk of prediabetes. We recommend that the results of this study be used to educate adults aged 40-64 yrs on diet and lifestyle habits to prevent diabetes.

Background/objectives: There is growing interest in herbal medicines for managing age-related diseases, such as Alzheimer's and Parkinson's. Safflower seeds (Carthamus tinctorius L. seeds, CTS) and dandelions (Taraxacum coreanum, TC) are widely used to treat bone- or inflammation-related diseases in Oriental countries. This study investigated the protective effect of the CTS-TC combination on scopolamine (Sco)-induced memory deficits through inflammatory response and cholinergic function. Moreover, marker components such as serotonin, N-(p-coumaroyl) serotonin, N-feruloylserotonin, chlorogenic acid, and chicoric acid in the CTS-TC combination were analyzed for their potential benefits on memory function.

Materials/methods: Water extracts of CTS, TC, and the CTS-TC combination at various ratios (4:1, 1:1, and 1:4) (100 mg/kg) were orally administered to mice for 14 days. Sco (1 mg/kg) was intraperitoneally injected into the mice before each behavioral test. T-maze and novel object recognition tests were conducted to monitor behavioral changes after the treatment. Western blotting was performed to detect protein expression. In addition, the presence of 5 biomarkers, serotonin, N-(p-coumaroyl) serotonin, N-feruloylserotonin, chlorogenic acid, and chicoric acid, was analyzed using high-performance liquid chromatography (HPLC).

Results: Behavioral tests showed that the CTS-TC combination enhanced memory function in Sco-injected mice. Inflammation-related proteins (inducible nitric oxide synthase, cyclooxygenase-2, and glial fibrillary acidic protein) were downregulated after treatment with the CTS-TC combination. The acetylcholinesterase protein expression was also downregulated. HPLC analysis revealed that N-feruloylserotonin and chicoric acid were the predominant components, followed by N-(p-coumaroyl) serotonin, chlorogenic acid, and serotonin.

Conclusion: These findings suggest that the CTS-TC combination protects against Sco-induced memory deficits by inhibiting inflammatory responses and cholinergic dysfunction. N-feruloylserotonin and chicoric acid, along with N-(p-coumaroyl) serotonin, chlorogenic acid, and serotonin, might be biomarkers for the CTS-TC combination, and their effects on memory protection warrant further study.

Background/objectives: Atherosclerosis particularly due to high circulating level of low-density lipoprotein is a major cause of cardiovascular diseases. Ellagic acid is a natural polyphenolic compound rich in pomegranates and berries. Our previous study showed that ellagic acid improved functionality of reverse cholesterol transport in murine model of atherosclerosis. The aim of this study is to investigate whether ellagic acid inhibited inflammation-associated atherosclerotic plaque formation in cholesterol-fed apolipoprotein E (apoE)-knockout (KO) mice.

Materials/methods: Wild type mice and apoE-KO mice were fed a cholesterol-rich Paigen diet for 10 weeks to induce severe atherosclerosis. Concurrently, 10 mg/kg ellagic acid was orally administered to the apoE-KO mice. Plaque lesion formation and lipid deposition were examined by staining with hematoxylin and eosin, Sudan IV and oil red O.

Results: The plasma leukocyte profile of cholesterol-fed mice was not altered by apoE deficiency. Oral administration of ellagic acid attenuated plaque lesion formation and lipid deposition in the aorta tree of apoE-KO mice. Ellagic acid substantially reduced plasma levels of soluble vascular cell adhesion molecule and interferon-γ in Paigen diet-fed apoE-KO mice. When 10 mg/kg ellagic acid was administered to cholesterol-fed apoE-KO mice, the levels of CD68 and MCP-1 were strongly reduced in aorta vessels. The protein expression level of nitric oxide synthase-2 (NOS2) in the aorta was highly enhanced by supplementation of ellagic acid to apoE-KO mice, but the expression level of heme oxygenase-1 (HO-1) in the aorta was reduced. Furthermore, ellagic acid diminished the increased aorta expression of the inflammatory adhesion molecules in cholesterol-fed apoE-KO mice. The treatment of ellagic acid inhibited the scavenger receptor-B1 expression in the aorta of apoE-KO mice, while the cholesterol efflux-related transporters were not significantly changed.

Conclusion: These results suggest that ellagic acid may be an atheroprotective compound by attenuating apoE deficiency-induced vascular inflammation and reducing atherosclerotic plaque lesion formation.

Background/objectives: The high consumption of purine-rich meat is associated with hyperuricemia. However, there is limited evidence linking the consumption of red and processed meat to the genetic risk of hyperuricemia. We investigated the relationship between various combinations of red and processed meat consumption and the polygenic risk scores (PRSs) and the incidence of hyperuricemia in middle-aged Koreans.

Subjects/methods: We analyzed the data from 44,053 participants aged ≥40 years sourced from the Health Examinees (HEXA) cohort of the Korean Genome and Epidemiology Study (KoGES). Information regarding red and processed meat intake was obtained using a semiquantitative food frequency questionnaire (SQ-FFQ). We identified 69 independent single-nucleotide polymorphisms (SNPs) at uric acid-related loci using genome-wide association studies (GWASs) and clumping analyses. The individual PRS, which is the weighted sum of the effect size of each allele at the SNP, was calculated. We used multivariable Cox proportional hazards models adjusted for covariates to determine the relationship between red and processed meat intake and the PRS in the incidence of hyperuricemia.

Results: During an average follow-up period of 5 years, 2,556 patients with hyperuricemia were identified. For both men and women, the group with the highest red and processed meat intake and the highest PRS was positively associated with the development of hyperuricemia when compared with the group with the lowest red and processed meat intake and the lowest PRS (hazard ratio [HR], 2.72; 95% confidence interval [CI], 2.10-3.53; P < 0.0001; HR, 3.28; 95% CI, 2.45-4.40; P < 0.0001).

Conclusion: Individuals at a high genetic risk for uric acid levels should moderate their consumption of red and processed meat to prevent hyperuricemia.

Background/objectives: Poly-γ-glutamic acid (γ-PGA), a natural polymer found in fermented soybean products, has been reported to play a prebiotic role in the gut. This intervention study investigated the effects of γ-PGA-containing supplement consumption on urinary microbiota in healthy adults because of limited data on such investigation.

Subjects/methods: A 4-week parallel trial including 39 male and female Korean adults, who were free of chronic diseases and infection, was designed as a randomized, double-blinded, placebo-controlled study. A total of 30 participants completed the study wherein the intervention group (n = 17) received a mixture supplement containing 600 mg/day of γ-PGA and 100 mg/day of vitamin B6, while the control group (n = 13) received a placebo. Paired datasets (baseline and endpoint data) of microbiota profiles, which were constructed via urinary assays of microbe-derived extracellular vesicles, were analyzed and compared between the two groups.

Results: Only the intervention group yielded significant results for the Bray-Curtis and Jaccard dissimilarity indices between baseline and endpoint data (P < 0.05). In the phylum-level analysis of microbial composition, the Firmicutes to Bacteroidetes ratio (FB ratio) tended to decrease from baseline in the intervention group; however, it increased in the control group. Differences between the baseline and endpoint FB ratios were significant between the two groups (P < 0.05).

Conclusion: This study's findings suggest that γ-PGA-vitamin B6 supplementation potentially alters the microbial community composition of a host. Further investigation into the biological consequences of commensal microbiota alteration by γ-PGA-containing supplement consumption is warranted.

Background/objectives: This study investigated the relationship between adolescent food-related lifestyles and food-related media use and eating behavior in Korea.

Subjects/methods: Participants were 392 Korean adolescents, ranging in age from 12 to 18, recruited via convenience sampling. They completed a self-report questionnaire survey consisting of questions about food-related lifestyle, food-related media use, food consumption behavior, food literacy, and nutrition quotient. Data analysis was conducted using SPSS 29.0. (IBM Co., Armonk, NY, USA).

Results: The factor analysis of food-related lifestyles identified four factors. Based on the cluster analysis results, participants were classified into three clusters reflecting different levels of interest: high interest in food, moderate interest in food, and low interest in food. The analysis revealed significant differences between groups in food-related liestyle factors (P < 0.05). Notably, the high-interest group demonstrated proactive engagement with food-related content, a willingness to explore diverse culinary experiences, and a conscientious consideration of nutritional labeling during food purchases. In contrast, the low-interest group reported tendencies toward overeating or succumbing to stimulating food consumption post-exposure to food-related content, coupled with a disregard for nutritional labeling when making food choices. A stronger inclination toward a food-related lifestyle was positively correlated with higher levels of food literacy and nutrition quotient.

Conclusion: This study proposes that the implementation of a nutrition education program using media could effectively promote a healthy diet among adolescents with a high level of interest in their dietary habits. For adolescents with low interest in their dietary habits, it suggests that introducing an education program with a primary focus on enhancing food literacy could be beneficial in fostering a healthy diet. Our research findings provide insight for the development of tailored nutritional education programs and establishment of effective nutrition policies.

Background/objectives: Cladophora glomerata extract (CGE), rich in polyphenols, was reported to exhibit antidiabetic and renoprotective effects by modulating the functions of protein kinases-mediated organic anion transporter 1 (Oat1) and 3 (Oat3) in rats with type 2 diabetes mellitus (T2DM). Nevertheless, the antioxidant effects of CGE on such renoprotection have not been investigated. This study examined the mechanisms involved in the antioxidant effects of CGE on renal organic anion transport function in an in vivo study.

Materials/methods: Diabetes was induced in the rats through a high-fat diet combined with a single dose of 40 mg/kg body weight (BW) streptozotocin. Subsequently, normal-diet rats were supplemented with a vehicle or 1,000 mg/kg BW of CGE, while T2DM rats were supplemented with a vehicle, CGE, or 200 mg/kg BW of vitamin C for 12 weeks. The study evaluated the general characteristics of T2DM and renal oxidative stress markers. The renal organic transport function was assessed by measuring the para-aminohippurate (PAH) uptake using renal cortical slices and renal inflammatory cytokine expression in the normal diet (ND) and ND + CGE treated groups.

Results: CGE supplementation significantly reduced hyperglycemia, hypertriglyceridemia, insulin resistance, and renal lipid peroxidation in T2DM rats. This was accompanied by the normalization of high expressions of renal glutathione peroxidase and nuclear factor kappa B by CGE and vitamin C. The renal anti-inflammation of CGE was evidenced by the reduction of tumor necrosis factor-1α and interleukin-1β. CGE directly blunted sodium nitroprusside-induced renal oxidative/nitrosative stresses and mediated the PAH uptake in the normally treated CGE in rats was particularly noteworthy. These data also correlated with reduced nitric oxide production, highlighting the potential of CGE as a therapeutic agent for managing T2DM-related renal complications.

Conclusion: These findings suggest that CGE has antidiabetic effects and directly prevents diabetic nephropathy through oxidative/nitrosative stress pathways.

Background/objectives: UV radiation is a major factor contributing to DNA damage in skin cells, including stem cells and mesenchymal stem cells, leading to the depletion of these crucial cells. This study examined whether a mixture of Indian gooseberry and barley sprout (IB) could inhibit UVB irradiation and 3-isobutyl-1-methylxanthine (IBMX)-induced photoaging and oxidative stress in the skin using HaCaT, Hs27, and B16F10 cells.

Materials/methods: The moisturizing-related factors, the collagen synthesis-related c-Jun N-terminal kinase (JNK)/c-Fos/c-Jun/matrix metalloproteinases (MMPs) pathway, and the melanogenesis-related cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/cAMP-responsive binding protein (CREB)/melanocyte inducing transcription factor (MITF)/tyrosinase-related protein (TRP)/tyrosinase activation pathways were analyzed in vitro by an enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blot analysis.

Results: The IB complex increased the hyaluronic acid and sphingomyelin levels and the collagenase inhibitory activity, enhanced hydration-related factors, including collagen, hyaluronic acid synthase (HAS), elastin, long chain base subunit 1 (LCB1) (serine palmitoyltransferase; SPT), and delta 4-desaturase sphingolipid 1 (DEGS1), modulated the inflammatory cytokines levels, antioxidant enzyme activities and the NF-κB/MMPs/cyclooxygenase-2 (COX-2) pathway in UVB-irradiated HaCaT cells, and inhibited wrinkle formation by down-regulation of the JNK/c-Fos/c-Jun/MMP pathway and up-regulation of the transforming growth factor-β receptor I (TGFβR1)/small mothers against decapentaplegic homolog (Smad3)/procollagen type І pathway in UVB-irradiated Hs27 cells. Moreover, the IB complex prevented melanin production by down-regulating the PKA/CREB/MITF/TRP-1/TRP-2 pathway in IBMX-induced B16F10 cells.

Conclusion: These findings suggest that the IB complex has the potential to serve as a safeguard, shielding the skin from UVB radiation-induced photo-damage.

Background/objectives: Mukbang, a trend originating in South Korea and gaining global popularity, could influence children's food choices and eating habits. This study analyzed the correlation between Mukbang viewing time in children and adolescents, their meal consumption frequency, nutrition quotient (NQ), and frequency of food intake.

Subjects/methods: From July to August 2022, this cross-sectional study investigated upper elementary students (ages 9-11 yrs) and adolescents (aged 12-18 yrs) using an online survey. The survey items included key demographic factors, Mukbang viewing frequency and duration, frequency of main meal consumption, commonly consumed foods, and the validated NQ, which was used to assess food intake quality. Multiple linear regression analysis was used to explore the link between Mukbang viewing and nutritional habits.

Results: Weekly Mukbang viewing time was significantly correlated with eating habits after adjusting for gender, age, physical activity frequency past week, household income, and primary caregiver's level of education. Increased Mukbang viewing time correlated with reduced frequency of breakfast (P for trend < 0.001) and dinner (P for trend = 0.012), while the frequency of eating out (P for trend < 0.001) and late-night snacking (P for trend = 0.008) increased. Higher Mukbang viewing time notably decreased scores in the moderation domain (P for trend < 0.001), in the practice domain (P for trend = 0.031), and overall NQ (P for trend < 0.001). It also significantly elevated intake of sweets (P for trend = 0.001), Korean-style street food, Western-style fast food, instant noodles, sweetened beverages, caffeinated beverages, and fruit and vegetable juices (P for trend < 0.001).

Conclusion: This study identifies a negative correlation between Mukbang viewing and eating habits among Korean children and adolescents. The results indicate the importance of incorporating children and adolescents' media usage and environmental factors on dietary education and the development of policy programs.