Blood ascorbic acid (AsA) concentrations are lower in diabetic patients than in the general population, a phenomenon that is also observed in streptozotocin (STZ)-diabetic models of type 1 diabetes. However, the occurrence of diabetes in KK-Ay mice, a model for type 2 diabetes, the most common form of diabetes, remains unclear. Although this mouse can synthesize AsA, understanding its level changes during diabetes progression could help in analyzing AsA’s effects on type 2 diabetes. Therefore, the present study investigated the relationship between hyperglycemia and AsA concentrations in the blood and organs of KK-Ay mice, and discussed the findings in relation to those observed in STZ-diabetic mice. Male KK-Ay mice were examined at different stages of diabetes (pre-diabetic, early onset, and hyperglycemic maintenance). STZ-diabetic mice were generated by administering STZ to ICR mice. AsA concentrations were measured in plasma, blood mononuclear cells, and tissues, along with hepatic L-gulonolactone oxidase (GLO) activity and mRNA expression levels. Unexpectedly, AsA concentrations in KK-Ay mice increased under hyperglycemic conditions, while they decreased in STZ-diabetic mice. A consistent relationship was not observed between organ AsA concentrations and hyperglycemia. GLO activity and mRNA expression levels increased in KK-Ay mice, but decreased in STZ-diabetic mice, suggesting an innate defense mechanism against hyperglycemia in KK-Ay mice. These results indicate that different diabetes models exhibit distinct changes in AsA concentrations and hepatic GLO activity under hyperglycemic conditions, highlighting the importance of considering endogenous AsA when evaluating the antioxidant properties of dietary components in KK-Ay mice.

Post-traumatic wound infection is commonly observed in trauma patients and has a poor prognosis. Vitamin D is a significant modulator of the immune system and may play a role in preventing wound infection. However, the inherent limitations and inconsistent results of previous observational studies restricted them from inferring causal effects. We employed Mendelian randomization design to estimate the causal effects of serum 25-hydroxyvitamin D levels on the risk of post-traumatic wound infection. Data in the analysis were extracted from large-scale genome-wide association studies with 417,580 individuals for serum 25-hydroxyvitamin D measurements and 218,546 individuals for post-traumatic wound infection. Multivariable Mendelian randomization analyses were performed to adjust for confounding variables. We also conducted extensive sensitivity analyses to verify the main results. The results revealed a causal relationship between higher serum 25-hydroxyvitamin D levels and a lower post-traumatic wound infection risk (OR=0.473, p=0.014). The causality remained after adjustment of potential confounding factors according to Multivariable Mendelian randomization analyses (OR=0.361, p<0.001). Sensitivity tests suggested the reliability of our findings. This study indicated a causal association between genetically predicted high serum 25-hydroxyvitamin D levels and a decreased risk of post-traumatic wound infection.

Terrestrial green plants are rich in phylloquinone (PK), and their PK content is highly correlated with the chlorophyll content. However, there are few studies on the PK content of algae and its correlation with chlorophyll content. To evaluate the PK content in algae and its correlation with chlorophyll, the PK and chlorophyll contents in algae, including Phaeophyta (18 species), Rhodophyta (17 species), and Chlorophyta (seven species), were determined. Algae, particularly Phaeophyta, contain more functional components than do other green terrestrial plants. Therefore, other components such as carotenoids, polyphenols, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability were analyzed to confirm their correlation with PK. Furthermore, terrestrial plants such as leafy vegetables, other vegetables, and tea powder were evaluated for the same components and compared with the experimental results for algae. This results showed that PK was abundant in Phaeophyta and almost all samples contained more than 100 μg/100 g of dry samples. In particular, Sargassum muticum contained 514.11±11.29 μg/100 g. However, almost all of the Rhodophyta and Chlorophyta contained a little PK. The results also confirmed a positive correlation between the PK and chlorophyll content in Rhodophyta (R²=0.7085), Chlorophyta (R²=0.7264), and terrestrial plants (R²=0.8436). However, no correlation was observed between the PK and chlorophyll content in Phaeophyta (R²=0.1013). In addition, the principal component analysis results showed no correlation between PK and other components, such as carotenoids and polyphenols, and DPPH radical scavenging ability in algae. However, Phaeophyta also contained more functional components, such as carotenoids, polyphenols, and DPPH radical scavenging ability than the other algal groups.

The aim was to evaluate the acute effect of drinking tomato juice preloaded with lemon and perilla oil 10 min before consuming carbohydrate on postprandial blood glucose, insulin, and lipids concentrations in young healthy women. In this randomized controlled crossover study, 21 women (age 21.1±0.6 y, HbA1c 5.2±0.2%, mean±SD) consumed either 200 g of tomato juice, tomato juice with 10 g of lemon juice and 5 g of perilla oil (n-3 PUFA-rich oil), or water 10 min before consuming 200 g of boiled white rice for 3 separate days. The energy and fat in tomato juice with lemon/n-3 PUFA-rich oil were higher (energy 402 kcal, fat 5.6 g) than tomato juice (354 kcal, 0.6 g) and water (315 kcal, 0.6 g). The blood parameters were measured at 0, 30, 60, and 120 min after carbohydrate consumption and compared among 3 d. The plasma glucose at 30 min in tomato juice with lemon/n-3 PUFA-rich oil was significantly lower than that of water (103.1±3.4 mg/dL vs. 127.8±4.0 mg/dL, p<0.001, mean±SE) and tended to be lower than that of tomato juice (113.9±4.9 mg/dL, p=0.078). The serum insulin at 30 min was also significantly lower in tomato juice with lemon/n-3 PUFA-rich oil than that of tomato juice (p<0.01). Adding lemon and n-3 PUFA-rich oil to tomato juice before carbohydrate meal can be practical method to lower early postprandial glucose and insulin responses in young healthy women.

Hypocarnitinemia is thought to exacerbate heart failure by impairing mitochondrial function and increasing oxidative stress. While some studies suggest that elevated acylcarnitine levels are linked to cardiovascular events, limited data are available on the relationship between free carnitine levels and clinical outcomes in heart failure patients. This study aimed to investigate the association between free carnitine levels and clinical outcomes in patients hospitalized for heart failure. This retrospective study included 271 consecutive patients admitted to our hospital for their first episode of acute heart failure. Patients were divided into four quartiles based on free carnitine levels (quartile 1: <37.0 μmol/L, n=69; quartile 2: 37.0–49.7 μmol/L, n=68; quartile 3: 49.7–58.9 μmol/L, n=67; quartile 4: ≥58.9 μmol/L, n=67). The primary endpoints were 1-y cardiac mortality, rehospitalization due to heart failure, and its composite endpoint. The incidence of cardiovascular events was compared among the quartiles. Creatinine levels were significantly higher in quartile 4 than in other groups. There were no significant differences in age or BNP among the four groups. Additionally, the 1-y mortality rate was significantly higher in both quartile 1 and quartile 4, while the rehospitalization rate for heart failure within 1 y post-discharge was significantly higher in quartile 4. In summary, the relationship between free carnitine levels and mortality in heart failure patients showed a J-curve pattern, with both low and high levels associated with worse outcomes. Thus, extreme free carnitine levels may serve as potential risk factors for adverse clinical outcomes in this population.

The research assessed calcium (Ca) and phosphorus (P) metabolism and microinflammation in malnourished uremic patients, focusing on the severity of vascular calcification, and examined the relationship between Ca and P metabolism indicators and microinflammation and the severity of vascular calcification. Seventy-eight patients undergoing hemodialysis treatment for ≥6 mo were collected. General information and anthropometric and blood biochemical indices were recorded, including gender, age, body mass index, mid-arm muscle circumference, albumin, intact parathyroid hormone, and Ca and P product (Ca×P). The severity of vascular calcification was graded. The correlation between the severity of vascular calcification in patients and each of the clinical indicators was analyzed. The diagnostic value of Ca and P metabolism and microinflammatory factors for vascular calcification in malnourished uremic patients was assessed. All enrolled patients were divided into a non-vascular calcification group (n=42) and a vascular calcification group (n=36) according to coronary artery calcification (CAC) scoring, and the probability of vascular calcification was 46%. The dialysis duration, Ca×P, P, hypersensitive C-reactive protein (hs-CRP), and interleukin 6 (IL-6) levels were significantly higher in the vascular calcification group than in the non-vascular calcification group. hs-CRP, IL-6, Ca×P, and P had predictive potency for vascular calcification in patients. CAC scores were correlated positively with hs-CRP, IL-6, Ca×P, and P. Malnourished uremic patients have a higher incidence of vascular calcification. hs-CRP, IL-6, Ca×P, and P are all independent risk factors for vascular calcification in uremic patients, and are positively correlated with the severity of vascular calcification.

Calcium and vitamin D have been suggested to be associated with the amelioration of symptoms of premenstrual syndrome (PMS). However, evidence for an association between the dietary intake of these nutrients and PMS is limited and inconsistent. We examined the cross-sectional association of calcium and vitamin D intake with PMS. Participants were 390 women aged 22–49 y who responded to a mail survey in 2022–2023. Dietary intake was assessed using a validated self-administered diet history questionnaire. PMS were assessed using the Premenstrual Symptoms Questionnaire. Logistic regression analysis was used to estimate odds ratios of PMS according to tertiles of calcium and vitamin D intake with adjustment for potential confounding variables. The prevalence of moderate to severe PMS was 10% (39 women). Neither calcium nor vitamin D intake was significantly associated with PMS. However, calcium intake was associated with a decreased prevalence of PMS, albeit without statistical significance, with multivariable-adjusted odds ratios (95% CI) for PMS in the lowest through highest tertiles of calcium intake of 1.00 (reference), 0.47 (0.18–1.25), and 0.27 (0.07–1.08), respectively (p for trend=0.06). The odds ratio of PMS was low in the highest tertile of vitamin D intake compared with the lowest, but without statistical significance (odds ratio 0.56, 95% CI 0.19–1.66). Our findings suggest that calcium and vitamin D intake was not appreciably associated with PMS. The suggestive inverse association between calcium intake and PMS requires further investigation.

In this study, we aimed at evaluating the effect of improving skin conditions on petal-derived blue rose extract (BRE) powder intake in middle-aged and older women in Japan. We conducted a randomized, double-blind, and placebo-controlled parallel study in 48 healthy Japanese women aged 40–50 y who were aware of dry skin. We divided the participants equally into two groups (i.e., 24–24 in the test and control groups, respectively). The participants consumed 100 mg either the placebo or BRE powder daily for 4 wk. We performed skin measurements before-and-after 4 wk of continuous intake. Upon 4 wk after continuous intake, the BRE group displayed improved skin quality compared with the control group. The primary outcome was stratum corneum water content, which significantly improved in the BRE group. The secondary outcomes, melanin index, stains, wrinkles, and rough texture showed improvements between the groups as well. Visual perception, roughness of texture, and wrinkles were improved between the groups. Finally, transparency yielded better scores within the groups. This study presents the results of the first functional test targeting BRE, unraveling various effect of improving skin condition and highlighting the potential of taking BRE in skin care.

Human body temperature homeostasis is regulated by both behavioral and autonomic thermoregulation. The transient receptor potential melastatin 8 (TRPM8) channel, a cold receptor, plays a critical role in cold perception and thermoregulation. Menthol, which activates TRPM8, has been shown to promote the “browning” of white adipocytes, enhancing thermogenesis. However, its effect on autonomic thermoregulation has remained unclear. To address this, the present study examines the influence of dietary menthol intake on autonomic thermoregulation in mice, with a focus on body temperature regulation under cold conditions. In this experiment, mice were fed diets containing 0.25% and 0.5% menthol for either 2 or 4 wk. The results indicated that the 0.5% menthol diet significantly reduced food intake, body weight, and visceral fat. In contrast, the 0.25% menthol diet showed no significant impact on these factors. Notably, mice treated with the 0.25% menthol diet for 4 wk suppressed the decrease in rectal and interscapular brown adipose tissue (IBAT) temperatures in a cold environment under anesthesia. Additionally, TRPM8 gene expression in IBAT was upregulated after 4 wk of 0.25% menthol diet consumption. These findings suggest that dietary menthol, especially at low concentrations, improves autonomic thermoregulation by activating TRPM8 without significantly affecting food intake or body weight.

We found indigo reductase homolog in Bacillus cohnii gene and succeeded in production of a large amount of the recombinant homolog in Escherichia coli. The homolog exhibited FMN-dependent NADPH-quinone reductase activity, but not indigo-reducing activity. Crystal structure analysis of the enzyme revealed the formation of a binary complex with FMN, 2-propanol, and glycerol, determined at a resolution of 1.57 Å. Notably, the structure of FMN was of particular interest, as the isoalloxazine ring of FMN exhibited a butterfly-like bent conformation, with an angular deviation of approximately 9.4º to 10.9º along the axis between N5 and N10. The reason for FMN adopting a butterfly-like structure was thought that the exposure of the enzyme crystal to X-ray radiation led to the one-electron reduction of FMN, forming the semiquinone radical FMNH^•.