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1.
The investigation was conducted on provision with vitamins C and B1 of Kyiv inhabitants limited contingent at spring period and efficiency of complex vitamin-mineral preparations in normalisation of the vitamins level in blood of human-subjects. The deficit of vitamin C in 54% and vitamin B1 in 18.5% of the investigated people was revealed. Supradin gave the best results among rest preparations ("Centrum", "Vitrum", "Duovit", "Multi-Tabs") in the normalization of the level of vitamin C and biologically-active form of thiamine (thiamindiphosphate) in the blood of investigated people.  相似文献   

2.
Vitamins B are co-enzymes participating in energy metabolic pathways. While some vitamins B are known affecting bone homeostasis, the effects of vitamin B1 (thiamine) on bone health remains unclear. In our study, we used cell counting kit-8, tartrate-resistant acid phosphatase stain, actin cytoskeleton stain, and pit formation assay to evaluate the effect of thiamine on osteoclast differentiation, formation, and function, respectively. Then we used dichloro-dihydro-fluorescein diacetate assay to investigate reactive oxygen species (ROS) generation and removal. Osteoporosis model by ovariectomy was established for animal experiments. We found that thiamine had inhibitory effect on osteoclast differentiation. And its inhibitory role on osteoclast differentiation is in a dose-dependent way. Mechanistically, ThDP suppresses intracellular ROS accumulation and unfolded protein response signaling during osteoclastogenesis via inhibiting Rac-Nox1/2/4 and intracellular inositol-requiring protein-1α/X-box-binding protein pathways, respectively. Osteoporotic mice treated with thiamine rich dietary showed better bone strength relative to thiamine deficient dietary. Our study explored the non-coenzyme inhibitory functions of B1 vitamin in receptor activator of nuclear factor κB ligand induced osteoclastogenesis and uncovered the significance of B1 vitamin in bone health.  相似文献   

3.
维生素是维持人体生命活动必需的一类有机物质,机体本身一般不能合成或合成量不足,因此需经食物或其他强化产品获取。目前,维生素产品已广泛应用于医药、食品添加剂、饲料添加剂、化妆品等领域,而且全球对维生素的需求也是呈逐年增长态势。维生素的生产方法主要包括化学合成法和生物合成法。化学合成法通常安全隐患大、反应条件严苛、废物污染严重,相比之下,代谢工程生产维生素绿色环保安全、能耗低,因此建立微生物细胞工厂具有重大的科学意义和应用需求。文中回顾了近30年来代谢工程在维生素生产领域的研究进展,详细阐述了水溶性维生素(维生素B1、B2、B3、B5、B6、B7、B9、B12和维生素C的前体)和脂溶性维生素(维生素A、维生素D的前体、维生素E和维生素K)的生物合成研究现状,并对其发酵生产的瓶颈进行了探讨,最后对合成生物技术创建维生素生产菌种进行了展望。  相似文献   

4.
Some ecologically important phytoplankters released vitamins into culture medium during growth. Skeletonema costatum and Stephanopyxis turris (vitamin B12-requirers) produced both thiamine (vitamin B1) and biotin when growing with either 12 or 2 ng vitamin B12/liter. Gonyaulax polyedra (vitamin B12-requirer) produced thiamine with 12 ng vitamin B12/liter, and Coccolithus huxleyi (thiamine-requirer) produced vitamin B12 and biotin with 120 ng thiamine/liter, but only biotin with 10 ng thiamine/liter. The amount of vitamin produced by an alga and rate at which it was produced varied with the phytoplankter, the concentration of the required vitamin, and incubation time. Vitamins produced during early and exponential growth were due to excretions, and those produced at stationary growth resulted from excretion and release due to cell lysis. Uptake of the required vitamin by all phytoplankters was greatest during the first few days of incubation. On continued incubation the rate of uptake/cell decreased. In the sea phytoplankters may contribute a major portion of the amount of dissolved vitamins.  相似文献   

5.
Vitamin B1 or thiamin is one of the B vitamins. All B vitamins help the body to convert food (carbohydrates) into fuel (glucose), which produces energy. The B vitamins are necessary for healthy skin, eyes, hair, and liver. It also could help the nervous system function properly, and is necessary for brain functions. Drug interactions with protein can affect the distribution of the drug and eliminate the drug in living systems. In this study, the binding of thiamine hydrochloride (vitamin B1) to bovine serum albumin (BSA) was evaluated using a new proposed vitamin B1 (thiamine)-selective membrane electrode under various experimental conditions, such as pH, ionic strength, and protein concentration; in addition molecular modeling was applied as well. The binding isotherms plotted based on potentiometric data and analyzed using the Wyman binding potential concept. The apparent binding constant was determined and used for the calculation of intrinsic Gibbs free energy of binding. According to the electrochemical and molecular docking results, it can be concluded that the hydrophobic interactions and hydrogen binding are major interactions between BSA and vitamin B1.  相似文献   

6.
Uptake and serosal transfer of the vitamins thiamine, riboflavin and folic acid have been studied in vivo in normal and parasitized rats infected with Hymenolepis diminuta (Cestoda). Regional differences in intestinal uptake of all three vitamins in both uninfected and parasitized animals were not satistically significant. In the parasitized intestine mucosal uptake and serosal transfer of thiamine were significantly inhibited, with increased mucosal accumulation of the vitamin as luminal thiamine concentration increased. Apparent increased riboflavin mucosal uptake in parasitized animals, was not matched by the reduced serosal transfer, suggesting adsorption of the vitamin in the unstirred aqueous layers. Mucosal uptake of folic acid increased in the parasitized gut; serosal transfer and mucosal accumulation were not affected. These results, indicating vitamin malabsorption associated with infection by H. diminuta, are consistent with the parasite inhibiting mucosal passive transport mechanisms. This conclusion is supported by the changes in net water fluxes associated with vitamin uptake in the parasitized intestine.  相似文献   

7.
Vitamins contain reactive functional groups necessary to their established roles as coenzymes and reducing agents. Their reactive potential may produce injury if vitamin concentration, distribution, or metabolism is altered. However, identification of vitamin toxicity has been difficult. The only well-established human vitamin neurotoxic effects are those due to hypervitaminosis A (pseudotumor cerebri) and pyridoxine (sensory neuropathy). In each case, the neurological effects of vitamin deficiency and vitamin excess are similar. Closely related to the neurological symptoms of hypervitaminosis A are symptoms including headache, pseudotumor cerebri, and embryotoxic effects reported in patients given vitamin A analogs or retinoids. Most tissues contain retinoic acid (RA) and vitamin D receptors, members of a steroid receptor superfamily known to regulate development and gene expression. Vitamin D3 effects on central nervous system (CNS) gene expression are predictable, in addition to the indirect effects owing to its influence on calcium and phosphorus homeostasis. Folates and thiamine cause seizures and excitation when administered in high dosage directly into the brain or cerebrospinal fluid (CSF) of experimental animals but have rarely been reported to cause human neurotoxicity, although fatal reactions to i.v. thiamine are well known. Ascorbic acid influences CNS function after peripheral administration and influences brain cell differentiation and 2-deoxyglucose accumulation by cultured glial cells. Biotin influences gene expression in animals that are not vitamin-deficient and alters astrocyte glucose utilization. The multiple enzymes and binding proteins involved in regeneration of retinal vitamin A illustrate the complexity of vitamin processing in the body. Vitamin A toxicity is also a good general model of vitamin neurotoxicity, because it shows the importance of the ratio of vitamin and vitamin-binding proteins in producing vitamin toxicity and of CNS permeability barriers. Because vitamin A and analogs enter the CNS better than most vitamins, and because retinoids have many effects on enzyme activity and gene expression, Vitamin A neurotoxicity is more likely than that of most, perhaps all other vitamins. Megadose vitamin therapy may cause injury that is confused with disease symptoms. High vitamin intake is more hazardous to peripheral organs than to the nervous system, because CNS vitamin entry is restricted. Vitamin administration into the brain or CSF, recommended in certain disease states, is hazardous and best avoided. The lack of controlled trials prevents us from defining the lowest human neurotoxic dose of any vitamin. Large differences in individual susceptibility to vitamin neurotoxicity probably exist, and ordinary vitamin doses may harm occasional patients with genetic disorders.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

8.
Essential vitamins for the growth of a cell line derived from the flesh fly, Sarcophaga peregrina, were determined. By examining the survivability of continuous passages of the cells in the chemically defined medium lacking one vitamin, thiamine, riboflavin, pantothenate and either niacin or niacinamide were found to be essential for the continuous growth of the flesh fly cells in vitro. [Originally published in Volume 37, Archives of Insect Biochemistry and Physiology, 37:283-286 (1998).] Copyright 1998 Wiley-Liss, Inc.  相似文献   

9.

Background

Vitamins involved in one-carbon metabolism are hypothesized to influence breast cancer (BC) risk. However, epidemiologic studies that examined associations between B vitamin intake and BC risk have provided inconsistent results. We prospectively examined, in the Italian ORDET cohort, whether B vitamin consumption was associated with risk of BC and BC subtypes.

Methods

After a mean follow-up of 16.5 years, 391 BCs were diagnosed among 10,786 cohort women. B vitamin intakes were estimated from food frequency questionnaires. Cox proportional hazard models adjusted for energy intake and confounders, estimated hazard ratios (HR) with 95% confidence intervals (CIs) for BC according to intake.

Results

RRs were 0.61 (95% CI 0.38–0.97 highest vs. lowest quartile; P trend 0.025) for thiamine; 0.48 (95% CI 0.32–0.71; P trend <0.001) for riboflavin; 0.59 (95% CI 0.39–0.90; P trend 0.008) for vitamin B6, and 0.65 (95% CI 0.44–0.95; P trend 0.021) for folate. As regards risk of BC subtypes, high riboflavin and folate were significantly associated with lower risk of estrogen receptor positive (ER+) and progesterone receptor positive (PR+) cancers, and high thiamine was associated with lower risk of ER-PR- cancers. High riboflavin was associated with lower risk of both HER2+ and HER2- cancers, high folate with lower risk of HER2- disease, and high thiamine with HER2+ disease.

Conclusions

These findings support protective effects of thiamine and one-carbon metabolism vitamins (folate, riboflavin, and vitamin B6) against BC in general; while folate may also protect against ER+PR+ and HER2- disease; and thiamine against ER-PR-, and HER2+ disease.  相似文献   

10.
The protective effect of Vitamins C, E and beta-carotene against gamma-ray-induced DNA damage in human lymphocytes in vitro was investigated. Cultured lymphocytes were exposed to increasing concentration of these vitamins either before or after irradiation with 2Gy of gamma-rays and DNA damage was estimated using micronucleus assay. A radioprotective effect was observed when antioxidant vitamins were added to cultured cells before as well after irradiation; the strongest effect was observed when they were added no later than 1h after irradiation. The radioprotective effect of vitamins also depended on their concentration; Vitamins C added at low concentration (1 microg/ml) before exposure of the cells to radiation prevented induction of micronuclei. Vitamin E at the concentration above 2 microg/ml decreased the level of radiation-induced micronuclei when compared to the cells irradiated without vitamin treatment. beta-Carotene was effective at all tested concentrations from 1 to 5 microg/ml and reduced the number of micronuclei in irradiated cells. The vitamins had no effect on radiation-induced cytotoxicity as measured by nuclear division index. The radioprotective action of antioxidant Vitamins C, E and beta-carotene was dependent upon their concentration as well as time and sequence of application.  相似文献   

11.
Vitamins are compounds that are essential for the normal growth, reproduction and functioning of the human body. Of the 13 known vitamins, vitamins A, D, E and K are lipophilic compounds and are therefore called fat‐soluble vitamins. Because of their lipophilicity, fat‐soluble vitamins are solubilized and transported by intracellular carrier proteins to exert their actions and to be metabolized properly. Vitamin A and its derivatives, collectively called retinoids, are solubilized by intracellular retinoid‐binding proteins such as cellular retinol‐binding protein (CRBP), cellular retinoic acid‐binding protein (CRABP) and cellular retinal‐binding protein (CRALBP). These proteins act as chaperones that regulate the metabolism, signaling and transport of retinoids. CRALBP‐mediated intracellular retinoid transport is essential for vision in human. α‐Tocopherol, the main form of vitamin E found in the body, is transported by α‐tocopherol transfer protein (α‐TTP) in hepatic cells. Defects of α‐TTP cause vitamin E deficiency and neurological disorders in humans. Recently, it has been shown that the interaction of α‐TTP with phosphoinositides plays a critical role in the intracellular transport of α‐tocopherol and is associated with familial vitamin E deficiency. In this review, we summarize the mechanisms and biological significance of the intracellular transport of vitamins A and E.   相似文献   

12.
Cognitive deficits have been observed in patients with multiple sclerosis (MS) due to hippocampal insults. Antioxidant vitamins D and E are suggested for patients suffering from neurodegenerative diseases like MS, while their mechanisms of action are not well understood. Here, we have tried to study the effects of these vitamins on demyelination, cell death, and remyelination of rat hippocampus following local ethidium bromide (EB) injection. Animals received 100 mg/kg vitamin E or 5 μg/kg of vitamin D3 for 2, 7, or 28 days. The extent of demyelination, myelin staining intensity, and expression of myelin basic protein and caspase-3 were investigated using histological and immunoblotting verification. Administration of EB alone caused demyelination, cell death, and afterward an endogenous repair. Vitamins E and D3 reduced the EB-induced damage and increased the endogenous remyelination of hippocampus. Although the anti-apoptotic effect of these vitamins and protection against demyelination were predictable based on their antioxidant effect, our results indicated the positive effect of vitamins E and D3 on process of remyelination by endogenous progenitor cells and supported their possible therapeutic effects in the context of demyelinating diseases like MS.  相似文献   

13.
  1. Chlorella ellipsoidea was grown synchronously and the changesin content of various vitamins during the algal life cycle werefollowed either by chemical or microbiological assay methods.
  2. In terms of µg per gram of cell dry weight, the contentof some vitamins (niacin, biotin, inositol and choline) remainedalmost constant throughout the algal life cycle, while thatof others (vitamin B6-complex, pantothenic acid, folic acid,thiamine and riboflavin) was found to decrease more or lessmarkedly during the "growing phase" and increase at later phasesof "ripening". The content of p-aminobenzoic acid increasedonly at an early stage of "ripening", and that of ascorbic acidincreased only at the stages in which photosynthesis occurredmost actively.
  3. These results were discussed in an attemptto interprete theirrelationship with the previously reportedobservations pertainingto the physiological and biochemicalevents occurring in thelife cycle of the alga.
(Received November 7, 1959; )  相似文献   

14.
The review deals with the scientific activity of the Department of Biochemistry of Lipids of the Palladin Biochemistry Institute of the National Academy of Sciences of Ukraine. The estimation of the functional role of some major lipids and of the minor lipid components, namely, N-acylethanolamines (NAE), is the main problem of the scientific investigations of the Department. The role of some lipids in the pathogenesis of diseases accompanied by the oxidative stress was also studied. The Department was the first to find and identify NAE in neuroblastoma C1300 N18 cells. It was shown that NAE with long saturated acyl chains inhibited veratridine-activated fast sodium channels. NAE also activated uterine plasma membrane smooth muscle Ca2+, Mg(2+)-ATPase, and inhibited Fe(2+)-induced free radical oxidation in mitochondria. The results of these investigations served as a basis for development of pharmacological substances with membrane protective properties. It was shown that, at different diseases accompanied by the oxidative stress, a significant change in the lipid composition of cell membranes occurred. Sometimes these changes were adaptive in character, which favored the cell viability adaptation to pathological conditions. The new level of regulation of adaptive reactions can be accompanied by the development of additive injuries of cell viability, which may be caused by the altered level of biologically active cell lipid components. Based on the results of these investigations, the preparation intended for treatment of male infertility was developed. The pharmacological substances intended for treatment of morphine abuse and acute ischemia of myocardium were created.  相似文献   

15.
Vitamins of the B-group viz., thiamine, riboflavin, pantothenicacid, pyridoxine and folic acid significantly increased theuptake of zinc by clusterbean and mustard plants. Vitamin inducedabsorptive capacity for zinc was greater in clusterbean thanin mustard. Uptake of Zn was maximum in leaves of pyridoxinetreated clusterbean and thiamine treated mustard plants. Zincuptake was found to be maximum at pH 9.0 and minimum at pH 6.0in both these two plants. The chelating agent (EDTA) was moreeffective in increasing Zn uptake in mustard than in clusterbean.A possible interaction between EDTA and vitamins is envisaged. Clusterbean, mustard, Zn uptake, B-vitamins, pH, EDTA  相似文献   

16.
The basic experimental data obtained at the Department of Coenzymes' Biochemistry of the A. V. Palladin Institute of Biochemistry of the Ukr. SSR Academy of Sciences as to the biological role of vitamin E are analyzed. Vitamin E, selenium and methionine are found to induce peculiar changes in the activity of glutathione-peroxidase, metabolism of sulphur-containing amino acids, biosynthesis of adenine nucleotides, proteins and nucleic acids. Participation of alpha-tocopherol and its active derivatives in the control of biosynthesis and intertransformation of ubiquinone and its cyclic isomer, ubichromenol, in the animal organism, is proved, which determines to a considerable extent the biological role of vitamin E in the bioenergy processes. It is substantiated in experiments that the detected wide range of the biological effect of vitamin E is associated with the control of RNA biosynthesis. Under these conditions the effect of vitamin E on the RNA synthesis does not depend on the manifestation of antioxidant properties of its molecule and in this sense it is a specific one. The results obtained are discussed for their significance in explanation of the molecular mechanism of the vitamin E action and in substantiation of the possibility to use the results in practical medicine and animal husbandry.  相似文献   

17.
E. B. Skvyrska was born in the town of Chigirin. In 1928 she graduated from the Agricultural-Pedagogical Division of the Kyiv Institute of People's Education (Taras Shevchenko Kyiv National University, now) in speciality pedagogue-biologist. In 1937 she finished the post-graduate course at the Institute of Biochemistry of the Academy of Sciences of the Ukrainian SSR, in 1940 she defended the thesis for the Candidate's degree in biology and the title of the senior researcher was conferred on her in 1941. Beginning from 1936, E. B. Skvyrska had been working at the Institute of Biochemistry. She was working at the Department of Structure and Biochemistry of Nervous System (till 1963), and then at the Department of Structure and Biochemistry of Nuclear Acids (till 1973). In 1958 she defended the thesis for the Doctor's degree. From 1938 to 1941 E. B. Skvyrska worked as the assistant, and from 1945 to 1950 as the docent of the Department of Biochemistry at the Taras Shevchenko Kyiv (State) National University. Up to 1941 her scientific work was dedicated to the investigation of peculiarities of carbohydrate metabolism of the central and peripheral nervous system depending on the animal age. Since 1951 E. B. Skvyrska was investigating the metabolism of high-molecular phosphorus-including compounds (nucleic acids, phosphoproteins and phospholipids) in the central nervous system during the excitation and inhibition, in ontogenesis, in functionally and morphologically different parts of the nervous system, in different structure elements of the nerve cell. The results of investigations allowed finding the biochemical peculiarities connected with the difference of structure and function of morphologically different divisions of the nervous system. Peculiarities and functioning of t-RNA and aminoacyl-t-RNA synthetases of rats in norm and during starvation were studied at the Department of Nucleic Acids. More than 50 scientific works have been published.  相似文献   

18.
Bloodstream forms of Trypanosoma brucei brucei were cultivated in the presence and absence of thiamine (vitamin B1) and pyridoxine (vitamin B6). The vitamins do not change growth behaviour, indicating that Trypanosoma brucei is prototrophic for the two vitamins even though in silico no bona-fide thiamine-biosynthetic genes could be identified in the T. brucei genome. Intracellularly, thiamine is mainly present in its diphosphate form. We were unable to detect significant uptake of [3H]thiamine and structural thiamine analogues such as pyrithiamine, oxithiamine and amprolium were not toxic for the bloodstream forms of T. brucei, indicating that the organism does not have an efficient uptake system for thiamine and its analogues. We have previously shown that, in the fission yeast Saccharomyces pombe, the toxicity of melarsen oxide, the pharmacologically active derivative of the frontline sleeping sickness drug melarsoprol, is abolished by thiamine and the drug is taken up by a thiamine-regulated membrane protein which is responsible for the utilization of thiamine. We show here that thiamine also has weak effects on melarsen oxide-induced growth inhibition and lysis in T. brucei. These effects were consistent with a low affinity of thiamine for the P2 adenosine transporter that is responsible for uptake of melaminophenyl arsenicals in African trypanosomes.  相似文献   

19.
The effect of exclusion of individual water-soluble (thiamine, riboflavin, pyridoxine, cyanocobalamin, pantothenic acid, folic acid, niacin, biotin, choline, inositol, ascorbic acid) and fat-soluble vitamins (vit. A, D, K and E) in semi-purified diets on growth and survival of juvenile shrimp, P. monodon was studied in the laboratory for 8 weeks. Diets lacking riboflavin and vitamin K did not affect growth and survival of shrimp. However, deletion of inositol and choline resulted in poor growth. Maximum growth was observed in the control diet (C1) which was supplemented with all vitamins. Diet deficient in ascorbic acid, biotin, folic acid, niacin, thiamine and alpha-tocopherol resulted in poor appetite and poorer feed conversion efficiency. All treatments except the control (C1) resulted in histological changes in the digestive gland cells. Detachment or destruction of the epithelial cells was observed in all treatments lacking individual vitamins but more severely in the treatment without a vitamin supplement followed by inositol, choline and ascorbic acid deficient diets.  相似文献   

20.
Our understanding of the molecular mechanisms responsible for fat-soluble vitamin uptake and transport at the intestinal level has advanced considerably over the past decade. On one hand, it has long been considered that vitamin D and E as well as β-carotene (the main provitamin A carotenoid in human diet) were absorbed by a passive diffusion process, although this could not explain the broad inter-individual variability in the absorption efficiency of these molecules. On the other hand, it was assumed that preformed vitamin A (retinol) and vitamin K1 (phylloquinone) absorption occurred via energy-dependent processes, but the transporters involved have not yet been identified. The recent discovery of intestinal proteins able to facilitate vitamin E and carotenoid uptake and secretion by the enterocyte has spurred renewed interest in studying the fundamental mechanisms involved in the absorption of these micronutrients. The proteins identified so far are cholesterol transporters such as SR-BI (scavenger receptor class B type I), CD36 (cluster determinant 36), NPC1L1 (Niemann–Pick C1-like 1) or ABCA1 (ATP-Binding Cassette A1) displaying a broad substrate specificity, but it is likely that other membrane proteins are also involved. After overviewing the metabolism of fat-soluble vitamins and carotenoids in the human upper gastrointestinal lumen, we will focus on the putative or identified proteins participating in the intestinal uptake, intracellular transport and basolateral secretion of these fat-soluble vitamins and carotenoids, and outline the uncertainties that need to be explored in the future. Identifying the proteins involved in intestinal uptake and transport of fat-soluble vitamins and carotenoids across the enterocyte is of great importance, especially as some of them are already targets for the development of drugs able to slow cholesterol absorption. Indeed, these drugs may also interfere with lipid vitamin uptake. A better understanding of the molecular mechanisms involved in fat-soluble vitamin and carotenoid absorption is a priority to better optimize their bioavailability.  相似文献   

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