menatetrenone has been researched along with Vitamin-K-Deficiency* in 24 studies
1 review(s) available for menatetrenone and Vitamin-K-Deficiency
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[Dementia and fracture].
A high incidence of fractures, particularly of the hip, represents an important problem in patients with AD, who are prone to falls and may have osteoporosis. The odds ratio reported for fracture prevalence between elderly persons with and without AD is 6.9. We previously demonstrated that deficiency of 25-hydroxyvitamin D due to sunlight deprivation and vitamin K deficiency due to malnutrition contributed to reduced bone mineral density in patients with AD and were associated with a high risk of hip fracture. Treatment with menatetrenone, risedronate or regular sunlight exposure are safe and effective in increasing bone mass and reducing the risk of hip fracture in patients with AD. Topics: Accidental Falls; Bone Density; Dementia; Etidronic Acid; Hip Fractures; Humans; Hyperparathyroidism, Secondary; Osteoporosis; Risedronic Acid; Risk; Risk Factors; Sunlight; Vitamin D Deficiency; Vitamin K 2; Vitamin K Deficiency | 2010 |
2 trial(s) available for menatetrenone and Vitamin-K-Deficiency
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Vitamin K administration to elderly patients with osteoporosis induces no hemostatic activation, even in those with suspected vitamin K deficiency.
The administration of menaquinone-4 (MK-4), one of subclasses of vitamin K2, significantly reduces bone loss in postmenopausal osteoporotic women. However, concerns have been raised about whether vitamin K administration alters the hemostatic balance by inducing a thrombotic tendency. We investigated were whether the administration of vitamin K in the form of MK-4 induced a thrombotic tendency in 29 elderly patients with osteoporosis (5 men, 24 women; age range 78.7+/-5.1 years). Patients were administered 45 mg/day (three times a day, 30 min after each meal) of MK-4 for 12 weeks. Blood samples were obtained from the patients at 0, 4 and 12 weeks after the start of MK-4 administration. A number of hemostatic parameters remained stable under the markedly increased plasma levels of MK-4. However, in patients with suspected vitamin K deficiency, whose plasma levels of vitamin K or factor VII were low, vitamin-K-dependent clotting factors such as factor VII and prothrombin were gradually increased after administration of MK-4. No changes in the sensitive molecular markers such as TAT and F1+2, which reflect the amount of thrombin generated in the blood stream, were observed, even in those patients with suspected vitamin K deficiency. These results indicate that MK-4 can be administered safely, with regard to maintaining the hemostatic balance, to osteoporotic patients receiving no anticoagulant therapy. Topics: Aged; Aged, 80 and over; Blood Coagulation Factors; Cyanoacrylates; Female; Hemostasis; Hemostatics; Humans; Male; Osteoporosis; Osteoporosis, Postmenopausal; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 2001 |
Menatetrenone ameliorates osteopenia in disuse-affected limbs of vitamin D- and K-deficient stroke patients.
Significant reduction in bone mineral density (BMD) occurs in stroke patients on the hemiplegic and contralateral sides, correlating with the degree of paralysis and vitamin D and K deficiency due to malnutrition, and increasing the risk of hip fracture. We evaluated the efficacy of vitamin K2 (menatetrenone: menaquinone-4; MK-4) in maintaining BMD by comparing serum biochemical indices of bone metabolism between treated and untreated patients. In a random and prospective study, of 108 hemiplegic patients following stroke, 54 received 45 mg menatetrenone daily (MK-4 group, n = 54) for 12 months, and the remaining 54 (untreatment group) did not. Nine patients excluded from the study. The BMD in the second metacarpals and serum indices of bone metabolism were determined. BMD on the hemiplegic side increased by 4.3% in the MK-4 group and decreased by 4.7% in the untreated group (p < 0.0001), while BMD on the intact side decreased by 0.9% in the MK-4 group and by 2.7% in the untreated group (p < 0.0001). At baseline, patients of both groups showed vitamin D and K1 deficiencies, high serum levels of ionized calcium, pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), and low levels of parathyroid hormones (PTH) and bone Gla proteins (BGP), indicating that immobilization-induced hypercalcemia inhibits renal synthesis of 1, 25-dihydroxyvitamin D (1, 25-[OH]2D) and compensatory PTH secretion. Both vitamins K1 and K2 increased by 97.6% and 666.9%, respectively, in the MK-4 group. Correspondingly, a significant increase in BGP and decreases in both ICTP and calcium were observed in the MK-4 group, in association with a simultaneous increase in both PTH and 1, 25-[OH]2D. One patient in the untreated group suffered from a hip fracture, compared with none in the MK-4 group. The treatment with MK-4 can increase the BMD of disused and vitamin D- and K-deficient hemiplegic bone by increasing the vitamin K concentration, and it also can decrease calcium levels through inhibition of bone resorption, resulting in an increase in 1, 25-[OH]2D concentration. Topics: Aged; Biomarkers; Bone Density; Bone Diseases, Metabolic; Cerebrovascular Disorders; Female; Hemiplegia; Hemostatics; Humans; Male; Metacarpus; Middle Aged; Prospective Studies; Vitamin D Deficiency; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1998 |
21 other study(ies) available for menatetrenone and Vitamin-K-Deficiency
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Controllable vitamin K deficiency under high-dose oral menatetrenone administration - a case report.
Vitamin (V) K deficiency may cause severe bleeding tendencies, which necessitates extreme caution. We report a case of a 30-year-old man diagnosed with VK deficiency of unknown etiology. He was treated with intravenous menatetrenone three times a week in an outpatient setting for about 1 year and 9 months. Eventually, he developed an allergic reaction to intravenous menatetrenone and was under steroid therapy. In order to reduce his hospital visits and discontinue steroid use, the pharmacist proposed to change the method of menatetrenone administration from intravenous to oral (high dose). The change in treatment method has greatly improved the patient's quality of life. Topics: Administration, Intravenous; Administration, Oral; Adult; Drug Hypersensitivity; Hemostatics; Humans; Male; Quality of Life; Steroids; Vitamin K 2; Vitamin K Deficiency | 2018 |
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. Topics: alpha-Tocopherol; Animals; Biomarkers; Bone and Bones; Bone Density; Bone Development; Diet; Dietary Supplements; Energy Metabolism; Gene Expression Regulation, Developmental; Liver; Male; Organ Specificity; Osteocalcin; Rats, Wistar; Specific Pathogen-Free Organisms; Tibia; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency; Vitamin K Deficiency Bleeding; Weight Gain | 2018 |
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. Topics: alpha-Tocopherol; Animals; Diet; Fermented Foods; Liver; Male; Nutritional Status; Rats, Wistar; Tissue Distribution; Vitamin K 1; Vitamin K 2; Vitamin K 3; Vitamin K Deficiency | 2018 |
Synthesis of 2-methyl-1,4-naphthoquinones with higher gamma-glutamyl carboxylase activity than MK-4 both in vitro and in vivo.
Vitamin K is the collective term for compounds that share a 2-methyl-1,4-naphthoquinone ring, but differ in the side-chain at the 3-position. We synthesized novel 2-methyl-1,4-naphthoquinone derivatives with different side chain length at the 3-position. Derivatives with C-14 and C-16 tails showed the highest in vitro bioactivity resulting in 2.5 and 2-fold higher carboxylated osteocalcin synthesis in MG63 cells than menaquinone-4 (MK-4, form of vitamin K2). Longer side chain lengths resulted in lower bioactivity. The in vivo vitamin K activity of the C-14 tail derivative was further tested in WKY rats receiving a vitamin K-deficient diet that resulted in a 40% decrease of prothrombin activity. The C-14 tail derivative was able to counteract the effects on vitamin K deficiency induced by the diet and resulted in the complete restoration of prothrombin activity. Compared to naturally occurring forms of vitamin K, synthetic vitamin K derivatives may have higher bioactivity and different pharmacological characteristics that are more favorable for use as supplements or in clinical settings. Topics: Animals; Carbon-Carbon Ligases; Cell Line, Tumor; Enzyme Activators; Humans; Molecular Structure; Osteocalcin; Prothrombin; Rats, Inbred WKY; Vitamin K; Vitamin K 2; Vitamin K Deficiency | 2017 |
Excess α-tocopherol decreases extrahepatic phylloquinone in phylloquinone-fed rats but not menaquinone-4 in menaquinone-4-fed rats.
The effects of vitamin E on vitamin K metabolism were elucidated by comparing the effect of tocopherol intake on vitamin K concentrations in rats fed phylloquinone (PK) or menaquinone (MK)-4.. Initially, the dietary effect of RRR-α-tocopherol, but not RRR-γ-tocopherol, in decreasing extrahepatic PK concentrations was confirmed. Subsequently, rats were fed a PK or MK-4-containing diet (0.75 mg/kg) with RRR-α-tocopherol (0, 10, 50, or 500 mg/kg) for 6 weeks. In rats fed PK, α-tocopherol consumption decreased PK in kidney, lung, heart, muscle, testis, and brain but not in serum and liver. However, in rats fed MK-4, α-tocopherol consumption did not decrease MK-4 in serum and tissues. Finally, vitamin K- and E-depleted rats were administered PK or MK-4 (0.2 mg) with RRR-α-tocopherol (0, 1, or 10 mg) by gavage. After PK administration, α-tocopherol was observed to decrease PK in kidney, adrenal gland, lung, testis, and brain but not in serum and liver, whereas, after MK-4 administration, α-tocopherol did not affect MK-4 in serum and tissues.. Excess α-tocopherol decreased extrahepatic PK in rats fed PK but not MK-4 in rats fed MK-4. Topics: alpha-Tocopherol; Animals; Dietary Supplements; Down-Regulation; gamma-Tocopherol; Male; Organ Specificity; Rats, Wistar; Specific Pathogen-Free Organisms; Vitamin E Deficiency; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 2014 |
Deuterium-labeled phylloquinone fed to α-tocopherol-injected rats demonstrates sensitivity of low phylloquinone-containing tissues to menaquinone-4 depletion.
The influence of excess α-tocopherol (α-T) on tissue depletion of phylloquinone (PK) and menaquinone-4 (MK-4) was evaluated.. Rats (n = 5 per group) were fed deuterium-labeled PK (2 μmol/kg diet) for 17 days, thereby labeling the conversion from deuterium-labeled PK to d₄-MK-4. Then they were injected subcutaneously daily for the last 7 days with saline, vehicle, or α-T (100 mg/kg body weight). α-T injections (i) increased α-T concentrations by tenfold in liver, doubled them in plasma and most tissues, but they were unchanged in brain; (ii) increased the α-T metabolite, carboxyethyl hydroxychromanol (α-CEHC) concentrations: >25-fold in liver and kidney, tenfold in plasma and lung, and 50-fold in heart; brain contained detectable α-CEHC (0.26 ± 0.03 nmol/g) only in α-T-injected animals; and (iii) depleted most tissues' vitamin K. Compared with vehicle-injected rats, brains from α-T rats contained half the total vitamin K (10.3 ± 0.5 versus 21 ± 2 pmol/g, p = 0.0002) and one-third the d₄-MK-4 (5.8 ± 0.5 versus 14.6 ± 1.7 pmol/g, p = 0.0002). Tissues with high PK concentrations (liver, 21-30 pmol/g and heart, 28-50 pmol/g) were resistant to K depletion.. We propose that α-T-dependent vitamin K depletion is likely mediated at an intermediate step in MK-4 production; thus, tissues with high PK are unaffected. Topics: alpha-Tocopherol; Animals; Biotransformation; Brain; Deuterium; Injections, Subcutaneous; Kidney; Liver; Male; Neurons; Organ Specificity; Rats, Sprague-Dawley; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency; Vitamins | 2014 |
[Suspicious case of epidural hematoma due to coagulopathy caused by vitamin K deficiency associated with antibiotics].
We experienced a case of epidural hematoma caused by coagulopathy 3 days after surgery. A 72-year-old man, who had undergone a total gastrectomy, suffered from nausea and vomiting by ileus. He underwent repair of ileus under general anesthesia with thoracic epidural anesthesia. Three days after surgery, abnormal bleeding followed by disorder of prothrombin activity (PT) and activated partial thromboplastin time (aPTT) and paralysis due to thoracic epidural hematoma developed. It was suspected that these coagulopathies were the results of vitamin K deficiency. Vitamin K deficiency in this patient was considered to have been caused by cephem antibiotics containing N-methyl-thiotetrazole (NMTT) side chain and no oral intake of food for a few days preoperatively. The patient was treated with fresh frozen plasma and intravenous menatetrenon, which improved abnormal bleeding and disorder of PT and aPTT within 24hr. After a discussion with orthopedic consultants, we selected a conservative therapy rather than surgical removal of the hematoma. Thoracic epidural hematoma disappeared two months after surgery, but motor paralysis requiring rehabilitation remained. In conclusion, when patients have not eaten anything for a few days and antibiotics with an NMTT sidechain has been administered, care must be taken to prevent vitamin K deficiency and coagulopathy. Topics: Aged; Anesthesia, Epidural; Anesthesia, General; Carbapenems; Gastrectomy; Hematoma, Epidural, Spinal; Humans; Ileus; Infusions, Intravenous; Male; Plasma; Postoperative Complications; Stomach Neoplasms; Tetrazoles; Vitamin K 2; Vitamin K Deficiency | 2007 |
Vitamin K status of healthy Japanese women: age-related vitamin K requirement for gamma-carboxylation of osteocalcin.
Vitamin K deficiency is associated with low bone mineral density and increased risk of bone fracture. Phylloquinone (K1) and menaquinone 4 (MK-4) and 7 (MK-7) are generally observed in human plasma; however, data are limited on their circulating concentrations and their associations with bone metabolism or with gamma-carboxylation of the osteocalcin molecule.. The objectives were to measure the circulating concentrations of K1, MK-4, and MK-7 in women and to ascertain whether each form of vitamin K is significantly associated with bone metabolism.. Plasma concentrations of K1, MK-4, MK-7, undercarboxylated osteocalcin (ucOC; measured by using the new electrochemiluminescence immunoassay), intact osteocalcin (iOC), calcium, and phosphorus; bone-derived alkaline phosphatase activity; and concentrations of urinary creatinine, N-terminal telopeptide, and deoxypyridinoline were measured in healthy women (n = 396).. On average, MK-7 and MK-4 were the highest and lowest, respectively, of the 3 vitamers in all age groups. K1 and MK-7 correlated inversely with ucOC, but associations between nutritional basal concentration of MK-4 and ucOC were not observed. Multiple regression analysis indicated that not only K1 and MK-7 concentrations but also age were independently correlated with ucOC concentration and the ratio of ucOC to iOC. The plasma K1 or MK-7 concentration required to minimize the ucOC concentration was highest in the group aged > or =70 y, and it decreased progressively for each of the younger age groups.. The definite role of ucOC remains unclear. However, if submaximal gamma-carboxylation is related to the prevention of fracture or bone mineral loss, circulating vitamin K concentrations in elderly people should be kept higher than those in young people. Topics: Adult; Age Factors; Aged; Aged, 80 and over; Aging; Biomarkers; Bone and Bones; Bone Density; Carboxylic Acids; Female; Fractures, Bone; Humans; Japan; Middle Aged; Nutritional Requirements; Nutritional Status; Osteocalcin; Risk Factors; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency; Vitamins | 2006 |
Difference in the metabolism of vitamin K between liver and bone in vitamin K-deficient rats.
The difference between vitamin K metabolism in the liver and that in the bone of vitamin K-deficient rats was examined. After 17 d administration of vitamin K-deficient food, vitamin K in the liver was almost depleted, and prothrombin time (PT) was prolonged. Serum total osteocalcin level was slightly decreased by vitamin K deficiency, whereas serum undercarboxylated osteocalcin level did not change. The level of menaquinone (MK)-4 as well as that of phylloquinone was decreased, but approximately 40 % of the initial level still existed in the femur after the 17 d period. A single-dose administration of vitamin K (250 nmol/kg body weight) markedly increased vitamin K level in the liver but not in the femur. These results suggest that the turnover of vitamin K in the bone is slower than that in the liver, and bone metabolism may be little affected by the short period of intake of vitamin K-deficient food. However, intake of a larger amount of vitamin K is required for its accumulation in the bone than in the liver. Furthermore, the counteracting effect of MK-7 on prolonged PT in vitamin K-deficient rats was found to be higher than phylloquinone or MK-4. Topics: Animals; Bone and Bones; Cyanoacrylates; Indoleacetic Acids; Liver; Male; Osteocalcin; Partial Thromboplastin Time; Prothrombin Time; Rats; Rats, Sprague-Dawley; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 2002 |
Gender differences in hepatic phylloquinone and menaquinones in the vitamin K-deficient and -supplemented rat.
Gender differences in relation to vitamin K were investigated in the rat. Hepatic phylloquinone and menaquinone (MK-1 to MK-10) concentrations, gamma-carboxyglutamic acid (Gla) excretion, plasma phylloquinone and percent prothrombin were measured in male and female rats on a chow diet (24.5 ng phylloquinone and 8.8 microgram menadione), and on phylloquinone-deficient and -supplemented purified diets (0.38 and 1400 ng phylloquinone/g, respectively). Mean hepatic phylloquinone concentrations varied with dietary intake and ranged from 6.8+/-9.0 pmol/g in the deficient male, to 171. 1+/-56.9 pmol/g in the supplemented female. Menaquinones accounted for a large proportion of total vitamin K in the liver of males and females with MK-4, MK-6, and MK-10 present in highest concentrations. On the chow and supplemented diets, females had significantly higher MK-4, MK-6, and MK-10 concentrations in their livers (P<0.05). On the phylloquinone-deficient diet (-K1), hepatic phylloquinone, MK-4, and to a lesser extent MK-6 (but not MK-10) were significantly reduced (P<0.05). In the phylloquinone-supplemented male and female groups, which did not receive menadione during the experimental period, MK-4 increased above that in the chow groups suggesting synthesis of MK-4 from phylloquinone which was statistically significant in the female (P<0.01). A significant gender difference (P<0.05) was also observed for urinary Gla excretion with less Gla excreted by the females indicating that females may require less dietary phylloquinone than males of the same body weight. Topics: 1-Carboxyglutamic Acid; Animals; Chromatography, High Pressure Liquid; Diet; Humans; Liver; Male; Prothrombin; Rats; Rats, Sprague-Dawley; Sex Factors; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1999 |
Tissue distribution of K-vitamers under different nutritional regimens in the rat.
Two forms of vitamin K [phylloquinone (K1) and menaquinone-4 (MK-4)] were added to vitamin K-deficient rat food in varying amounts. These diets were given as the sole source of nutrition to rats for one week. The minimal dietary requirements (MDR) to attain maximal prothrombin synthesis were determined to be 0.6 and 6-10 microg/g of food for K1 and MK-4, respectively. The difference between both vitamers could be explained by the limited hepatic accumulation of MK-4. Next, vitamin K was offered to rats at concentrations ranging between 0.6 and 3000 microg/g of food, and the tissue distribution of vitamin K was investigated after one week of administration. Accumulation of K1 and MK-4 was found in all tissues investigated, but both the absolute tissue concentration and the ratio between K1 and MK-4 were tissue-dependent. Highest values were found in liver and in heart, but since the heart contains no gamma-glutamylcarboxylase, the function of vitamin K in this tissue remains obscure. High tissue concentrations of MK-4 were also found in pancreas and testis after a diet containing K1 exclusively. The data indicate that this conversion is tissue-specific, but neither the reason nor its mechanism are known. Topics: Animal Nutritional Physiological Phenomena; Animals; Carbon-Carbon Ligases; Diet; Dietary Supplements; Liver; Male; Myocardium; Prothrombin; Rats; Rats, Inbred Strains; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1998 |
Intestinal flora is not an intermediate in the phylloquinone-menaquinone-4 conversion in the rat.
To elucidate the role of intestinal bacteria in the conversion of phylloquinone into menaquinone-4 (MK-4) we investigated the tissue distribution of vitamin K in germ-free rats. The rats were made vitamin K deficient by feeding a vitamin K-free diet for 13 days. In a subsequent period of 6 days, phylloquinone and menadione were supplied via the drinking water in concentrations of 10 and 50 micromol l(-1). Menadione supplementation led to high levels of tissue MK-4, particularly in extrahepatic tissues like pancreas, aorta, fat and brain. Liver and serum were low in MK-4. Phylloquinone supplementation resulted in higher phylloquinone levels in all tissues when compared with vitamin K-deficient values. The main target organs were liver, heart and fat. Remarkably, tissue MK-4 levels were also higher after the phylloquinone supplementation. The MK-4 tissue distribution pattern after phylloquinone intake was comparable with that found after menadione intake. Our results demonstrate that the conversion of phylloquinone into MK-4 in extrahepatic tissues may occur in the absence of an intestinal bacterial population and is tissue specific. A specific function for extrahepatic MK-4 or a reason for this biochemical conversion of phylloquinone into MK-4 remains unclear thus far. Topics: Animals; Diet; Germ-Free Life; Intestines; Male; Rats; Rats, Wistar; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1998 |
Induction of prothrombin synthesis by K-vitamins compared in vitamin K-deficient and in brodifacoum-treated rats.
Vitamin K is a group name for a number of prenylated 2-methyl-1,4-naphtoquinones, which may differ in their ability to function as a cofactor for prothrombin biosynthesis. To quantify the bioactivity of different forms of vitamin K, two experimental animal systems are frequently used: vitamin K-deficient rats and anticoagulated rats. In this paper both models are compared, and it is shown that the results obtained depend on the model used. The main reason for this discrepancy is the difference in recycling of vitamin K-epoxide, which results in a 500 times higher vitamin K requirement in anticoagulated rats. Absorption and hepatic accumulation of long chain menaquinones seem to be restricted to a maximum, whereas also the lipophilic nature of long chain menaquinones may hamper the quinone-quinol reduction in anticoagulated animals. If these data may be extrapolated to patients, food items rich in K1 and MK-4 would be expected to influence the stability of oral anticoagulation to a much larger extent than food items primarily containing higher menaquinones. Topics: 4-Hydroxycoumarins; Absorption; Animals; Anticoagulants; Blood Coagulation; Disease Models, Animal; Male; Prothrombin; Rats; Rats, Inbred Lew; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1998 |
Modulation of arterial thrombosis tendency in rats by vitamin K and its side chains.
Vitamin K is involved in the biosynthesis of a number of blood coagulation factors and bone proteins. It has been suggested that the vitamin K requirement of bone tissue is higher than that of the liver. Here we report that in rats very high doses of vitamin K affected neither the blood coagulation characteristics nor the blood platelet aggregation rate. This was observed for both phylloquinone and menaquinone-4. Both vitamers were also tested for their effects on the arterial thrombosis tendency in the rat aorta loop model. The mean obstruction times were prolonged at a high intake of menaquinone-4 (250 mg/kg body weight/day), and shortened after a similarly high phylloquinone regimen. Since (a) both vitamers only differ in their aliphatic side chains; and (b) a similar trend was observed after administration of phytol and geranylgeraniol, we conclude that the modulation of the arterial thrombosis tendency is accomplished by the side chain of vitamin K. Topics: Animals; Blood Coagulation; Diet; Dietary Fats, Unsaturated; Disease Models, Animal; Disease Susceptibility; Diterpenes; Dose-Response Relationship, Drug; Male; Phytol; Platelet Aggregation; Rats; Rats, Wistar; Thrombosis; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1997 |
Bioavailability of phylloquinone and menaquinones after oral and colorectal administration in vitamin K-deficient rats.
Rats were made vitamin K-deficient by feeding them a diet devoid of vitamin K and by rigorously preventing coprophagy. After one week, circulating prothrombin concentrations were between 5 and 10% of initial values, and various amounts of phylloquinone, menaquinone-4, and menaquinone-9 were given in a single dose either subcutaneously, orally, or colorectally. The relative 'vitamin K activities' of these compounds were assessed by comparing their ability to support prothrombin synthesis after subcutaneous injection. Intestinal and colonic absorption were deduced from the difference between subcutaneous and either oral or colorectal administration of the vitamers. It is concluded that the colonic absorption of all three forms of vitamin K is extremely poor, suggesting that physiological menaquinones in the colon do not contribute substantially to vitamin K status in rats. Furthermore, the stimulation of prothrombin synthesis by menaquinone-9 lasted much longer than that by the two other K-vitamers, resulting in a substantially higher 'vitamin K activity' of menaquinone-9. Topics: Animals; Biological Availability; Hemostatics; Intestinal Absorption; Male; Prothrombin; Rats; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1995 |
Effects of menatetrenone on the decrease in calcium balance induced by vitamin K-deficient diet and sodium loading in rats.
The effects of menatetrenone (2-methyl-3-tetraprenyl-1,4-naphthoquinone, MK-4) on calcium balance were studied in male Sprague-Dawley rats. Experiment 1: Rats in metabolic cages that were fed a vitamin K-deficient diet and injected daily with latamoxef (100 mg/kg, i.p.) were either treated or untreated with MK-4 for 7 days. Daily food intake, urine volume and feces weight were determined, and calcium concentration in these samples was measured. Calcium balance was calculated as the difference between calcium intake and urinary and fecal calcium excretion. Cumulative calcium balance in the vitamin K-deficient group treated with latamoxef was lower than that in normal rats; this balance was significantly improved by MK-4 (1 and 10 mg/kg, s.c.) administered for 7 days. Experiment 2: Rats were fed a vitamin K-deficient diet containing 4.6% sodium chloride for 6 weeks. MK-4 was administered as a dietary supplement. Forty-eight-hour calcium balance, determined once a week, was significantly reduced compared with that of normal rats after 3 and 5 weeks; the balance was restored dose-dependently by MK-4 administration (1 and 10 mg/kg). Experiment 3: Rats were subjected to the same experimental conditions as experiment 2 for 6 weeks, and intestinal calcium transport was determined using an everted gut-sac technique. Calcium transport was reduced by the high sodium, vitamin K-deficient diet, and this reduction was restored by MK-4 administration (10 mg/kg). These results suggest that MK-4 improves the reduced calcium balance by increasing intestinal calcium absorption in these rats. Topics: Alkaline Phosphatase; Animals; Blood Coagulation; Calcium; Diet; Hemostatics; Intestinal Absorption; Intestinal Mucosa; Intestines; Kidney Function Tests; Male; Phosphates; Rats; Rats, Sprague-Dawley; Sodium; Vitamin K; Vitamin K 2; Vitamin K Deficiency | 1994 |
The relative effects of phylloquinone and menaquinone-4 on the blood coagulation factor synthesis in vitamin K-deficient rats.
Rats were made vitamin K-deficient by feeding them a 1:1 (w/w) mixture of a commercial vitamin K-depleted diet and boiled white rice. After one week of treatment the rats had developed severe vitamin K deficiency, resulting in Thrombotest values of 5-10% of the initial values. In this experimental system the efficacy of phylloquinone (K1) was compared with that of menaquinone-4 (MK-4) by measuring the extent to which the Thrombotest was normalized after the administration of varying doses of the respective vitamins. Oral administration of the vitamins showed that the efficacy of K1 was at least two-fold higher than that of MK-4. As comparable results were obtained after subcutaneous administration of the vitamins, we conclude that after oral administration the intestinal absorption had been quick and nearly complete. A less pronounced effect of K1 and MK-4 was found after colorectal administration. For both forms of vitamin K relatively high amounts (well above the physiological concentration) were required before significant effects on the Thrombotest could be observed. Therefore these data demonstrate the importance of sufficient dietary vitamin K consumption in rats. The efficacy of other menaquinones may be investigated in the same experimental animal model system. Topics: Administration, Oral; Animals; Blood Coagulation Factors; Injections, Subcutaneous; Male; Rats; Rats, Inbred Lew; Rectum; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1993 |
The roles of intestinal flora and intestinal function on vitamin K metabolism.
Topics: Administration, Oral; Animals; Germ-Free Life; Intestines; Male; Mice; Mice, Inbred ICR; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1992 |
Changes of plasma des-gamma-carboxy prothrombin levels in patients with hepatocellular carcinoma in response to vitamin K.
The effect of menaquinone-4 (MK-4, vitamin K2) was studied on des-gamma-carboxy prothrombin (DCP or PIVKA-II) levels in three subjects with vitamin K deficiency and five patients with hepatocellular carcinoma (HCC) with positive DCP. The half-life of DCP in HCC patients after intravenous MK-4 administration (50 mg daily for 14 days) was determined to be 60 hours, identical to that found in vitamin K-deficient subjects who received MK-4. When a single dose of MK-4 (10 mg) was given intravenously to three patients with HCC and elevated DCP, the levels decreased with a reduction rate identical to that in vitamin K-deficient subjects for the first 1 to 3 days, followed by an increase reaching the previous level in 7 to 10 days. Changes in plasma coagulant activity were compared between subjects with vitamin K deficiency and those with HCC before and after a single dose of MK-4 (10 mg). The activity increased in DCP-positive patients with HCC as in vitamin K-deficient subjects who received the same single dose of MK-4. The increase was greater in HCC patients with higher DCP levels. These results suggest that the level of plasma DCP in patients with HCC responded to vitamin K with the same sensitivity as that in vitamin K-deficient subjects. When patients with HCC underwent effective tumor therapy (resection or arterial embolization), the reduction rate (slope of DCP decline) was found to be identical to that in vitamin K-deficient subjects given with MK-4. In patients with less effective therapy, the reduction rate was smaller, or there was an increase in DCP. These observations strongly suggest that sequential measurements of the DCP reduction rate after treatment for HCC are useful for assessing therapeutic effects. Topics: Aged; Biomarkers; Carcinoma, Hepatocellular; Embolization, Therapeutic; Female; Half-Life; Humans; Liver Neoplasms; Male; Middle Aged; Protein Precursors; Prothrombin; Vitamin K; Vitamin K 2; Vitamin K Deficiency | 1992 |
Hepatic concentration of vitamin K active compounds after application of phylloquinone to chickens on a vitamin K deficient or adequate diet.
Liver and serum concentrations of vitamin K active compounds were measured in two groups of (deficient and normal) broilers after administration of phylloquinone 1 mg/kg. Assays were performed by HPLC after extraction and purification of these compounds. The only menaquinone found in the chicken was menaquinone-4. In the deficient group, the chickens exhibited hepatic concentrations of vitamin K1, vitamin K1 epoxide and menaquinone-4 markedly lower than those of the control group. After administration of phylloquinone, vitamin K and vitamin K epoxide levels fell sharply. There is no hepatic storage of vitamin K comparable to that of vitamin A. However, while menaquinone levels were found to be stable in the control group, they rose significantly in the deficient group after vitamin K injection. The question is: is there a transformation of vitamin K into menaquinone and/or is there a preferential utilization of one of the vitamin K active compounds? Topics: Animals; Chickens; Diet; Female; Injections, Intravenous; Liver; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1992 |
[Studies on transfer of vitamin K into human breast milk].
We studied whether the administration of vitamin K to mothers could increase the concentration of vitamin K in breast milk and prevent idiopathic vitamin K deficient bleeding in breast-feeding infants. Sixty puerperal women were divided into three groups, the control group, Menaquinone-4 (MK-4) administered group and vitamin K1 administered group. We measured the concentrations of vitamin K1, MK-4 and MK-7 in maternal plasma and breast milk on the fourth day after delivery. In the MK-4 group, the concentrations of MK-4(2.13 ng/ml in plasma, 49.3 ng/ml in milk) were significantly higher than in the control group (0.28 ng/ml, 1.51 ng/ml). In the vitamin K1 group, the concentrations of vitamin K1 (49.0 ng/ml in plasma, 71.6 ng/ml in milk) were significantly higher than in the control group (1.17 ng/ml, 2.41 ng/ml). The concentration rates (milk/plasma ratio) of vitamin K1, MK-4 and MK-7 were 2.52, 5.43 and 0.52 in the control group, 1.60, 40.2 and 0.67 in the MK-4 group and 1.65, 10.8 and 0.71 in the vitamin K1 group, respectively. The concentration rate of MK-4 was higher than that of vitamin K1 and was increased by MK-4 administration. After delivery, the daily concentration of MK-4 in milk was increased from 1.69 ng/ml on the first day to 49.3 ng/ml on the fourth day in the MK-4 group. These results indicate that MK-4 is accumulated and concentrated into breast milk, and continuous MK-4 administration can increase the concentration of vitamin K in milk, preventing idiopathic vitamin K deficient bleeding in infants. Topics: Female; Humans; Infant; Milk, Human; Postpartum Period; Pregnancy; Vitamin K; Vitamin K 1; Vitamin K 2; Vitamin K Deficiency | 1989 |