Tissue Distribution of Menaquinone-7 and the Effect of α-Tocopherol Intake on Menaquinone-7 Concentration in Rats

We have reported that vitamin E intake lowers phylloquinone (PK) concentration in extrahepatic tissues of rats. In this study, we aimed to clarify the characteristic of the distribution of menaquinone-7 (MK-7), a vitamin K contained in fermented foods, by comparison with other vitamin K distributions and to clarify the effect of vitamin E intake on MK-7 concentration in rats. Rats were fed a vitamin K-free diet (Free group), a diet containing 0.75 mg PK/kg (PK group), a 0.74 mg menaquinone-4 (MK-4)/kg diet (MK-4 group), a 1.08 mg MK-7/kg diet (MK-7 group), or a 0.29 mg menadione (MD)/kg diet (MD group) for 16 wk. MK-7 mainly accumulated in the liver, spleen, and adrenal gland of the MK-7 group, although PK accumulated in the serum and all tissues of the PK group. Conversely, MK-4 was present in all tissues of the PK, MK-4, MK-7, and MD groups. MK-4 concentration in the serum, liver, adipose tissue, and spleen was higher in the MK-4 group than in the other groups; however, MK-4 concentration in the kidney, testis, tibia, and brain was lower in the MK-4 group than in the PK, MK-7, and MD groups. Next, vitamin E- and K-deficient rats were orally administered MK-7 with or without α-tocopherol. α-Tocopherol did not affect MK-7 or MK-4 concentration in the serum and various tissues. These results suggested that MK-7 is particularly liable to accumulate in the liver, and MK-7 concentration is not affected by vitamin E intake.

γ-Tocopherol Is Metabolized Faster than α-Tocopherol in Young Japanese Women

To elucidate the characteristics of γ-tocopherol metabolism, serum concentrations of α- and γ-tocopherol, and urinary excretion of their metabolites after ingestion of α- or γ-tocopherol, major isoforms in our diet, were compared. Six healthy Japanese women (age 22.7±1.7 y old, BMI 21.4±0.9) ingested 134 mg of α- or γ-tocopherol, and blood and urine were collected until 72 h later. After α-tocopherol intake, the serum concentration of α-tocopherol increased at 12-24 h, and urinary excretion of 2,5,7,8-tetramethyl-2(2'-carboxyethyl)-6-hydroxychroman (α-CEHC), an α-tocopherol metabolite, increased at 12-36 h. However, after γ-tocopherol intake, the serum concentration of γ-tocopherol increased at 6-12 h, and excretion of 2,7,8-trimethyl-2(2'-carboxyethyl)-6-hydroxychroman (γ-CEHC), a γ-tocopherol metabolite, increased at 3-12 h. The area under the curve from 0 to 72 h and serum maximal concentration of γ-tocopherol were lower than those of α-tocopherol. The time to maximal concentration of γ-tocopherol was faster than that of α-tocopherol. The ratio of urinary excretion of carboxyethyl-hydroxychroman to tocopherol intake was 2.9% for α-CEHC and 7.7% for γ-CEHC. These results revealed that γ-tocopherol is metabolized faster than α-tocopherol in healthy young women.

Delayed first active-phase meal, a breakfast-skipping model, led to increased body weight and shifted the circadian oscillation of the hepatic clock and lipid metabolism-related genes in rats fed a high-fat diet

The circadian clock is closely related to human health, such as metabolic syndrome and cardiovascular disease. Our previous study revealed that irregular feeding induced abnormal lipid metabolism with disruption of the hepatic circadian clock. We hypothesized that breakfast skipping induces lipid abnormalities, such as adiposity, by altering the hepatic circadian oscillation of clock and lipid metabolism-related genes. Here, we established a delayed first active-phase meal (DFAM) protocol as a breakfast-skipping model. Briefly, rats were fed a high-fat diet during zeitgeber time (ZT) 12-24 in a control group and ZT 16-4 in the DFAM group. The DFAM group showed increased body weight gain and perirenal adipose tissue weight without a change in total food intake. The circadian oscillations of hepatic clock and de novo fatty acid synthesis genes were delayed by 2-4 h because of DFAM. The peaks of serum insulin, a synchronizer for the liver clock, bile acids, and non-esterified fatty acid (NEFA) were delayed by 4-6 h because of DFAM. Moreover, DFAM delayed the surge in body temperature by 4 h and may have contributed to the increase in body weight gain and adipose tissue weight because of decreased energy expenditure. These data indicated a potential molecular mechanism by which breakfast skipping induces abnormal lipid metabolism, which is related to the altered circadian oscillation of hepatic gene expression. The results also suggested that the delayed peaks of serum NEFA, bile acids, and insulin entrain the circadian rhythm of hepatic clock and lipid metabolism-related genes.

α-Tocopherol Intake Decreases Phylloquinone Concentration in Bone but Does Not Affect Bone Metabolism in Rats

Previous studies have shown that α-tocopherol intake lowers phylloquinone (PK) concentration in some extrahepatic tissues in rats. The study's aim was to clarify the effect of α-tocopherol intake on vitamin K concentration in bone, as well as the physiological action of vitamin K. Male Wistar rats were divided into 4 groups. Over a 3-mo period, the K-free group was fed a vitamin K-free diet with 50 mg RRR-α-tocopherol/kg, the E-free group was fed a diet containing 0.75 mg PK/kg without vitamin E, the control group was fed a diet containing 0.75 mg PK/kg with 50 mg RRR-α-tocopherol/kg, and the E-excess group was fed a diet containing 0.75 mg PK/kg with 500 mg RRR-α-tocopherol/kg. PK concentration in the liver was higher in E-excess rats than in E-free rats, was lower in the tibias of control rats than in those of E-free rats, and was lower in E-excess rats than in control rats. Menaquinone-4 (MK-4) concentration in the liver was higher in E-excess rats than in E-free and control rats. However, MK-4 concentrations in the tibias of E-free, control, and E-excess rats were almost the same. Blood coagulation activity was lower in K-free rats than in the other rats but was not affected by the level of α-tocopherol intake. Additionally, dietary intake of PK and α-tocopherol did not affect uncarboxylated-osteocalcin concentration in the serum, femur density, or expression of the genes related to bone resorption and formation in the femur. These results suggest that α-tocopherol intake decreases PK concentration in bone but does not affect bone metabolism in rats.

Defects in centromeric/pericentromeric histone H2A T120 phosphorylation by hBUB1 cause chromosome missegregation producing multinucleated cells

Histone H2A phosphorylation plays a role both in chromatin condensation during mitosis and in transcriptional activation during the G1/S transition. Bub1 and NHK1/VRK1 have been identified as histone H2A kinases. However, little is known about the importance of histone H2A phosphorylation in chromosome segregation. Here, we expressed recombinant hBUB1 and confirmed that it phosphorylates histone H2A T120 in the in vitro-assembled nucleosome. Knockdown (KD) of BUB1 decreases bulk H2A T120 phosphorylation in HeLa cells, whereas hBUB1 is upregulated during mitosis, which corresponds with H2A T120 phosphorylation. ChIP-qPCR of the DXZ1 centromeric and γ-ALR pericentromeric region showed that BUB1 localizes to this region and increases local H2A T120 phosphorylation during M phase. BUB1 KD did not induce apoptosis but increased the M phase cell population, as detected by flow cytometry. BUB1 KD also caused an abnormal metaphase and telophase, resulting in multinucleated cells and impaired cancer cell growth both in vitro and in vivo. Over-expression of the histone H2A T120D or T120E mutations, which mimic phosphorylated threonine, decreased the number of multinucleated cells caused by BUB1 KD. These results strengthen the apparent importance of BUB1-mediated H2A T120 phosphorylation in normal mitosis.

Time-restricted feeding suppresses excess sucrose-induced plasma and liver lipid accumulation in rats

The etiology of metabolic syndrome involves several complicated factors. One of the main factors contributing to metabolic syndrome has been proposed to be excessive intake of sucrose, which disturbs hepatic lipid metabolism, resulting in fatty liver. However, the mechanism by which sucrose induces fatty liver remains to be elucidated. Considering feeding behavior important for metabolism, we investigated whether time-restricted feeding of high sucrose diet (HSD), only in the active phase (the dark phase of the daily light/dark cycle), would ameliorate adverse effects of sucrose on lipid homeostasis in rats. Male Wistar rats, fed either an ad libitum (ad lib.) or time-restricted control starch diet (CD) or HSD were investigated. Rats fed ad lib. (CD and HSD) completed approximately 20% of food intake in the daytime. Time-restricted feeding did not significantly suppress total food intake of rats. However, time-restricted feeding of HSD significantly suppressed the increased plasma triglyceride levels. Moreover, time-restricted feeding also ameliorated HSD-induced liver lipid accumulation, whereas circadian oscillations of liver clock gene or transcriptional factor gene expression for lipid metabolism were not altered significantly. These results demonstrated that restricting sucrose intake only during the active phase in rats ameliorates the abnormal lipid metabolism caused by excess sucrose intake.

Effects of Dialysis Membranes on the Kinetics of Tumor Necrosis Factor-α Production by Peripheral Mononuclear Cells in Chronic Hemodialysis Patients

To evaluate the biocompatibility of dialysis membranes, blood samples were collected from 10 hemodialysis patients immediately before dialysis and peripheral blood mononuclear cells were isolated. The 3.0 x 105 cells/ml were then passed 30 times through modules made of a polyethylene glycolgrafted cellulose membrane, a polyacrylonitrile membrane, and a polysulfone membrane. Expression of messenger RNA for tumor necrosi factor-α (TNF-α) was determined. Cells were also cultured for 2 h with and without lipopolysaccharide and TNF-α levels in the supernatant were measured.

TNF-α messenger RNA expression was significantly higher immediately after passage through the polyacrylonitrile membrane compared with the other membranes. Cells cultured without lipopolysaccharide, produced significantly less TNF-α after passage through the polysulfone membrane, while lipopolysaccharide significantly increased TNF-α production by cells passed through the polyacrylonitrile membrane. These results suggest that biocompatibility differs even among dialysis membranes believed to cause no complement activation.

Usefulness of Immunoadsorption Therapy for Systemic Lupus Erythematosus Associated with Transverse Myelitis. A Case Report

Transverse myelitis (TM) is a very rare complication of systemic lupus erythematosus (SLE) and its prognosis is poor. It therefore needs to be treated aggressively. We describe a patient suffering from SLE associated with TM, who responded well to a combination of immunoadsorption therapy and steroid mini-pulse therapy. His serum interleukin 6 levels as well as clinical indicators fell to normal after this treatment.

Low-risk papillary microcarcinoma of the thyroid: A review of active surveillance trials

Papillary microcarcinoma (PMC) of the thyroid is defined as papillary thyroid carcinoma (PTC) measuring ≤1 cm. Many autopsy studies on subjects who died of non-thyroidal diseases reported latent small thyroid carcinoma in up to 5.2% of the subjects. A mass screening study for thyroid cancer in Japanese adult women detected small thyroid cancer in 3.5% of the examinees. This incidence was close to the incidence of latent thyroid cancer and more than 1000 times the prevalence of clinical thyroid cancer in Japanese women reported at that time. The question of whether it was correct to treat such PMCs surgically then arose. In 1993, according to Dr. Miyauchi's proposal, Kuma Hospital initiated an active surveillance trial for low-risk PMC as defined in the text. In 1995, Cancer Institute Hospital in Tokyo, Japan, started a similar observation trial. The accumulated data from the trials at these two institutions strongly suggest that active surveillance (i.e., observation without immediate surgery) can be the first-line management for low-risk PMC. Although our data showed that young age and pregnancy might be risk factors of disease progression, we think that these patients can also be candidates for active surveillance, because all of the patients who showed progression signs were treated successfully with a rescue surgery, and none of them died of PTC. In this review, we summarize the data regarding the active surveillance of low-risk PMC as support for physicians and institutions that are considering adopting this strategy.

Influence of various carbohydrate sources on postprandial glucose, insulin and NEFA concentrations in obese cats

Carbohydrate is an important source of energy, which can significantly affect postprandial blood glucose and insulin levels in cats. In healthy animals, this is not a big concern; however, in obese and diabetic animals, this is an important detail. In the present study, the impact of four different carbohydrate sources (glucose, maltose, corn starch, and trehalose) on short-term post-prandial serum glucose, insulin, and non-esterified fatty acid (NEFA) concentrations was investigated with four obese cats. Each of the carbohydrate sources was added to a commercial wet food diet for feeding the animals. A significant difference was observed in postprandial glucose, insulin, and NEFA area under the curve (AUC) values between each carbohydrate source in obese cats. Furthermore, glucose and maltose induced the highest postprandial glucose and insulin AUC values, whereas trehalose induced the lowest postprandial glucose and insulin AUC value amongst all carbohydrate sources, respectively, in obese cats. However, trehalose has a higher risk of inducing side effects, such as diarrhea, as compared to other carbohydrate sources. As such, different carbohydrate sources appear to have a very significant impact on post-prandial glycemia and subsequent insulin requirement levels in obese cats. These results might be useful when selecting a prescription diet for obese or diabetic cats. In addition, maltose appears to be capable of inducing experimentally evoked postprandial hyperglycemia in obese cats, which may serve as a good tool for use to check the impact and effectiveness of newly developed oral hypoglycemic drugs or supplements for cats in future experiments.

Evaluation of portable blood glucose meters using canine and feline pooled blood samples

This study evaluated the accuracy and reproducibility of a human portable blood glucose meter (PBGM) for canine and feline whole blood. Reference plasma glucose values (RPGV) were concurrently measured using glucose oxidation methods. Fifteen healthy dogs and 6 healthy cats were used for blood sampling. Blood glucose concentrations and hematocrits were adjusted using pooled blood samples for our targeted values. A positive correlation between the PBGM and RPGV was found for both dogs (y = 0.877, x = -24.38, r = 0.9982, n = 73) and cats (y = 1.048, x = -27.06, r = 0.9984, n = 69). Acceptable results were obtained in error grid analysis between PBGM and RPGV in both dogs and cats; 100% of these results were within zones A and B. Following ISO recommendations, a PBGM is considered accurate if 95% of the measurements are within ± 15 mg/dl of the RPGV when the glucose concentration is <100 mg/dl and within ±15% when it is ≥100 mg/dl; however, small numbers of samples were observed inside the acceptable limits for both dogs (11%, 8 of 73 dogs) and cats (39%, 27 of 69 cats). Blood samples with high hematocrits induced lower whole blood glucose values measured by the PBGM than RPGV under hypoglycemic, normoglycemic, and hyperglycemic conditions in both dogs and cats. Therefore, this device is not clinically useful in dogs and cats. New PBGMs which automatically compensate for the hematocrit should be developed in veterinary practice.