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PubMed2003

Tochu (Eucommia ulmoides) leaf extract prevents ammonia and vitamin C deficiency induced gastric mucosal injury.

The ingestion of dietary antioxidants, including vitamin C (VC), is suggested to play an important role in the prevention of gastric cancer associated with Helicobacter pylori (HP) infection. Recently, water extracts of Tochu (Du-zhong, Eucommia ulmoidea OLIVER) leaves (WETL) have been reported to have potent antioxidant and antimutagenic effects. The present study investigated the effect(s) of VC and WETL on gastric mucosal injury induced by ammonia and a VC deficient diet. Guinea pigs fed the water containing ammonia and/or a VC-deficient diet were simultaneously treated with WETL or VC. Intramucosal levels of thiobarubiturate reactive substances (TBARS), an index of lipid peroxidation, increased significantly in animals fed ammoniated water and VC-deficient diets. This was accompanied by accelerated cell proliferation and increases in immunohistochemical staining indices for oxidative stress-induced DNA adducts and strand breaks (e.g., BrdU-uptake, 8-OhdG, ssDNA and the TUNEL reaction). The administration of either WETL or VC to the ammoniated water and VC-deficient diets ameliorated the increases in intramucosal TBARS levels and labeling indices of BrdU, 8-OHdG, ssDNA and TUNEL, i.e., the levels were similar to those measured in the normal-fed control animals. These data suggest that insufficient VC ingestion may be an important risk factor for gastric cancer development in patients with HP infections. Furthermore, our results suggest that WETL or some constituent may contribute to the prevention of oxidative gastric injury that precedes carcinogenesis.

Ammonia↗

PubMedDate not supplied

[Effect of protein-vitamin deficiency on the enzyme activity of lipolysis and the synthesis of cholesterol esters during hypokinesia].

Balanced diet during 60-day hypokinesia leads to inhibition of lipoprotein lypase (LPLA) and liver triglyceride lypase (L-TGLA) activity of the rat blood serum. The level of very low density lipoproteins (VLDLP) grows, and suppression of lecithin-cholesteryl-acyltransferase (LCAT) activity is accompanied by reduction of the share of cholesterol derivatives with polyunsaturated fatty acids. Combined effects of protein-vitamin insufficiency and hypokinesia result in parversion of the lipolysis processes, that manifests in prevalence of L-TGLA over LPLA. The levels of VLDLP increase, and growth of LCAT activity is acompanied by the growth of cholesteryl linoleate share and level. Hypokinesia combined with the studied experimental diets was found to lead to increase of the free fatty acid level and to decrease of the blood serum levels of phospholipids and triglycerides.

Animals↗

PubMed1982

[Vitamins and trace elements in the elderly (author's transl)].

A review of published research data on the requirement, intake, and signs of deficiency of vitamins and trace elements in old age is presented. It particularly deals with the problem of a general indication for vitamins and trace element supplements - the mean components of geriatric preparations. Special emphasis is laid on the question if these substances exhibit a specific effect on the alterations of physical and psychic capacity typically accompanying the growing old. It could be shown that in several groups of the elderly diminished vitamin levels are common and/or vitamin and trace element intake does not reach daily recommended allowances. But it still remains unclear if these findings have to be considered as disease symptoms.

Aged↗

PubMed2005

Effect of a fortified maize-meal porridge on anemia, micronutrient status, and motor development of infants.

BACKGROUND: Maize-meal porridge is used for infant feeding in many African countries, including South Africa. A low-cost, finely milled, maize-meal porridge was fortified with beta-carotene, iron, and zinc (100% of recommended dietary allowance), as well as ascorbic acid, copper, selenium, riboflavin, vitamin B-6, vitamin B-12, and vitamin E. OBJECTIVE: We assessed whether the fortified porridge could reduce anemia and improve the micronutrient status and motor development of infants. DESIGN: Infants aged 6-12 mo (n = 361) were randomly assigned to receive either the fortified or unfortified porridge for 6 mo. Primary outcomes were hemoglobin and serum retinol, zinc, and ferritin concentrations and motor development. Growth was assessed as a secondary outcome. Primary and secondary outcomes were assessed at baseline and 6 mo. RESULTS: Two hundred ninety-two infants completed the study. The fortified-porridge group had an intervention effect of 9.4 microg/L (95% CI: 3.6, 15.1 microg/L) for serum ferritin and 9 g/L (95% CI: 6, 12 g/L) for hemoglobin concentrations. The proportion of infants with anemia decreased from 45% to 17% in the fortified-porridge group, whereas it remained >40% in the control group. The fortified-porridge group achieved on average 15.5 of the 25 motor development score items, whereas the control group achieved 14.4 items (P = 0.007). Serum retinol concentration showed an inconsistent effect, and no intervention effect was observed for serum zinc concentrations. CONCLUSIONS: This low-cost fortified porridge can potentially have a significant effect in reducing anemia and improving iron status and motor development of infants in poor settings. The formulation needs some adjustment in terms of zinc fortification.

Anemia, Iron-Deficiency↗

PubMedDate not supplied

Growth disorders and homocysteine metabolism.

Inherited disorders of homocysteine metabolism produce accelerated growth and arteriosclerosis with myointimal hyperplasia. The growth of cell cultures from cystathionine synthetase deficient individuals with homocystinuria is characterized by abnormal contact inhibition and production of an aggregated proteoglycan matrix which binds excess sulfate. Homocysteic acid, a precursor of sulfate ester, increases the growth rate of normal guinea pigs. Synthesis of homocysteic acid from homocysteine thiolactone is more rapid in the livers of young animals than adults, and hypophysectomy results in a pattern of homocysteine thiolactone metabolism resembling that in liver of adult animals. Homocysteine thiolactone metabolism differs in guinea pig, an herbivorous species, and in rat, an omnivorous species. Sulfate binding by cultured human cells is slightly increased when homocysteic acid is present in the culture medium. These observations suggest a relationship between homocysteic acid and somatomedin, a serum polypeptide which mediates the action of growth hormone. The growth disorders associated with homocystinuria, including arteriosclerosis and accelerated growth, are believed to result from increased conversion of methionine to homocysteine thiolactone and homocysteic acid.

Age Factors↗

PubMed1986

Ascorbic acid chronic alcohol consumption in the guinea pig.

Protection against the toxic effects of chronic alcohol consumption was observed in male guinea pigs maintained on a high-ascorbic-acid diet (vitamin C-deficient chow plus 2.0 mg ascorbic acid/ml drinking water) as compared to animals on a low-ascorbic-acid diet (vitamin C-deficient chow and from 0.025 to 0.050 mg ascorbic acid/ml drinking water). Alcohol was orally administered to the guinea pigs at a dose of 2.5 g/kg for up to 14 weeks. Levels of serum aspartate aminotransferase and serum alanine aminotransferase were significantly elevated in animals on the low-ascorbic-acid diet that received alcohol, 120 and 250%, respectively. In contrast, in animals on the high-ascorbic-acid diet that received alcohol, levels of alanine aminotransferase were not significantly elevated and levels of aspartate aminotransferase were elevated 50%. In addition, some of the animals on the low-ascorbic-acid diet that received alcohol for 12 to 14 weeks developed hepatic steatosis and necrosis, whereas none of the animals on the high-ascorbic-acid diet that received alcohol for the same length of time manifested these changes.

Administration, Oral↗

PubMed1990

Vitamin C deficiency in captive nonhuman primates fed commercial primate diet.

Scurvy was diagnosed in 19 rhesus monkeys (Macaca mulatta) and four squirrel monkeys (Saimiri sciureus) from a colony of nonhuman primates maintained on a commercial diet. Signs of weakness, reluctance to move, gingival hemorrhage, bruising, proximal and distal metaphyseal fractures, weight loss and anemia appeared in juvenile and young adult rhesus monkeys over a 2 week period. Clinical signs subsided after 5 days of vitamin C therapy. At the same time, cephalohematomas and weakness developed in squirrel monkeys, which failed to respond to treatment. These cases were associated with manufacturer's admitted error in preparation of the commercially prepared monkey diet.

Anemia↗

PubMed1975

Diogenes syndrome. A clinical study of gross neglect in old age.

A study of elderly patients (fourteen men, sixteen women) who were admitted to hospital with acute illness and extreme self-neglect revealed common features which might be called Diogenes syndrome. All had dirty, untidy homes and a filthy personal appearance about which they showed no shame. Hoarding of rubbish (syllogomania) was sometimes seen. All except two lived alone, but poverty and poor housing standards were not a serious problem. All were known to the social-services departments and a third had persistently refused offers of help. An acute presentation with falls or collapse was common, and several physical diagnoses could be made. Multiple deficiency states were found--including iron, folate, vitamin B12, vitamin C, calcium and vitamin D, serum proteins and albumin, water, and potassium. The mortality, especially for women, was high (46%); most of the survivors responded well and were discharged. Half showed no evidence of psychiatric disorder and possessed higher than average intelligence. Many had led successful professional and business lives, with good family backgrounds and upbringing. Personality characteristics showed them to tend to be aloff, suspicious, emotionally labile, aggressive, group-dependent, and reality-distorting individuals. It is suggested that this syndrome may be a reaction late in life to stress in a certain type of personality.

Age Factors↗

PubMed1988

Deficiencies of vitamins in CAPD patients: the effect of supplementation.

Concentrations of the vitamins B1, B2, B6, B12, C, folic acid, A, E and beta-carotene were determined in blood and 24-h dialysate in 44 CAPD patients. Twenty-five of these patients were studied during chronic treatment (mean 313 days, range 60-1034 days). Nineteen patients were studied during training. In a longitudinal study, 11 patients were analysed again after 77-507 (mean 238) days. In both patient groups a considerable portion of patients (11%-64%) had blood concentrations indicative of a deficiency of the vitamins B1, B6, C and folic acid. The average concentrations of these vitamins were normal in both groups. The only abnormal finding was the mean EGOT activity being deficient in patients on chronic treatment. Mean concentrations of vitamin A were above normal in both groups. In the longitudinal study a significant increase of vitamin B2 and a decrease of vitamin B6 in blood was found. When compared to 24-h excretion in normal urine, loss with 24-h dialysate was low for vitamin B1, normal to relatively high for vitamin B2 and B6, but extremely high for vitamin C and folic acid. The vitamins B12, A, E and carotenoids were hardly detectable in the dialysate. In ten other patients the effect of daily supplementation with 2 mg vitamin B6, 100 mg vitamin C and 400 micrograms folic acid was analysed during a 16-week period. In all patients a significant increase in blood concentrations was obtained. It is concluded that these dosages were sufficient to maintain a normal status of these vitamins in CAPD patients.

Adult↗

PubMed2004

Genome stability of vtc1, tt4, and tt5 Arabidopsis thaliana mutants impaired in protection against oxidative stress.

Reactive oxygen species (ROS) are formed upon normal cellular metabolism or influence of environmental factors and, at normal levels, they play an important physiological role. However, at elevated levels, radicals are toxic and extremely dangerous to all cellular components, including DNA. To efficiently protect themselves, plants have developed sophisticated mechanisms for radical screening and scavenging. In this paper, we analyzed the genome stability of several plant mutants impaired in the protection against free radicals. We crossed the well-known uidA recombination reporter line 651 to flavonoid (tt4 and tt5) and Vitamin C (vtc1)-deficient plants. We found that in all lines tested, both spontaneous and induced (UVC and Rose Bengal (RB)) recombination was higher than in the original 651 parental line. The mRNA expression levels of various DNA repair (RAD1, RAD54-like, MSH3) as well as radical scavenging genes (GPx1, CAT, FSD3) exhibited substantial differences in both control and induced conditions. Our data show that plants impaired in certain aspects of the protection against elevated levels of free radicals induce the production of scavenging enzymes earlier than wild-type (wt) plants, and the higher level of radical species results in the increased incidence of spontaneous double-strand breaks resulting in a higher expression of DNA repair genes.

Arabidopsis↗

PubMed1997

Ascorbate deficiency and oxidative stress in the alveolar type II cell.

The objective of this study was to determine the impact of limited ascorbate (Asc) availability on type II cell sensitivity to oxidant stress. Guinea pigs were fed diets with or without Asc for 18 days, and type II cells were isolated. Although lung Asc was decreased by 90% in deficient animals (scorbutic), type II cell Asc was decreased by 50%. Upon treatment with 250 microM H2O2, the necrotic injury was twofold greater in scorbutic cells compared with control cells. With 100 microM H2O2 treatment, apoptotic injury was twofold greater in scorbutic cells compared with control cells. Although there was less necrotic injury in cells exposed to 95% O2, the scorbutic cells were more sensitive than control cells. Asc pretreatment protected against necrosis and apoptosis. The Asc analog isoascorbate provided partial protection and suggested that part of the protection was not chemical detoxification but was Asc specific. We conclude that limited Asc availability resulted in a functional type II cell but a cell more sensitive to oxidant-induced injury.

Animals↗

PubMed1992

Marginal nutritional status among institutionalized elderly women as compared to those living more independently (Dutch Nutrition Surveillance System).

The nutritional status (assessed by anthropometric indices, and biochemical and hematological variables in blood) of three groups of elderly women (aged > or = 65 years) was evaluated within the framework of the Dutch Nutrition Surveillance System. The groups were composed of women living in a nursing home (n = 51), women living in service flats and receiving their dinners from the nursing home kitchen (n = 29), and women living independently (n = 52). Mean blood levels of folate, pyridoxal 5'-phosphate, 25-hydroxyvitamin D, alpha-tocopherol, vitamin C, albumin, selenium and total cholesterol were significantly (p < 0.05) lower among nursing home women. Among these women a biochemical deficiency was frequently found for 25-hydroxyvitamin D (73%), pyridoxal 5'-phosphate (57%), vitamin C (38%), selenium (30%) and folate (28%). These nutritional risks were largely independent of each other. Since folate and pyridoxal 5'-phosphate were associated with several clinicochemical indicators, health status may be an important determining factor for this unfavorable situation. Low 25-hydroxyvitamin D concentrations were associated with limited exposure to ultraviolet radiation and nonusage of vitamin D supplements. We conclude that dietary intake variables are not the only determinants of a marginal nutritional status among nursing home women. Use of foods with a high nutrient density should be encouraged, whereas other preventive measures are needed to improve vitamin D status.

Aged↗

PubMed1998

Vitamin C status of a campus population: college students get a C minus.

Diet and the vitamin C status of two samples of college students were examined. Nonsmoking participants were recruited from a campus population during the fall and winter months. The prevalence of vitamin C deficiency (plasma vitamin C concentrations less than 11 mumol/L) ranged from 1% to 2% in the sampled campus populations. Marginal vitamin C status (plasma vitamin C concentrations from 11 to less than 28 mumol/L) was observed in 12% of the fall sample and 16% in the winter sample. Participants with marginal vitamin C status consumed significantly fewer servings of fruits and vegetables daily than participants with adequate vitamin C status. Marginal vitamin C status, which is even more pronounced in smokers, has been associated with fatigue and increased severity of respiratory tract infections. Because the vitamin C status of many college students, both smokers and nonsmokers, may be inadequate, health promotion or wellness programs for all students should emphasize the importance of adequate fruit and vegetable consumption.

Adult↗

PubMed1985

[Vitamin C deficiency in patients in a nursing home].

The Dutch Nutrition Council recommends an average daily intake of at least 50 mg of vitamin C. In a Dutch centre for nursing and rehabilitation this amount in the food as consumed by 272 patients and as served by the kitchen was calculated to be below 20 mg. About half of the patients consumed additional food - rich in vitamin C - each day either bought or acquired. Symptoms pertaining to the disease scorbut, were observed in a considerable number of these patients, but these may also be caused by other diseases. Patients completely dependent on food served by the central kitchen, had very low values of plasma vitamin C, in contrast to patients who used extra fruit each day. Centres for nursing and rehabilitation are recommended to serve 150 ml vitamin C-rich fruit juice each day, thereby combining the advantages of providing enough fluid intake and preventing obstipation.

Aged↗

PubMed1998

Plasma vitamins A, C and E in the general population of Singapore, 1993 to 1995.

The National University of Singapore Heart Study measured cardiovascular risk factors, including selected plasma vitamins, on a random sample of the general population aged 30 to 69 years. Plasma vitamins A and E were normal and similar by ethnic group. Mean plasma vitamin A levels were: Chinese (males 0.68 and females 0.52 mg/L), Malays (males 0.67 and females 0.54 mg/L), and Indians (males 0.66 and females 0.51 mg/L). Mean plasma vitamin E levels were: Chinese (males 12.6 and females 12.6 mg/L), Malays (males 13.6 and females 13.3 mg/L), and Indians (males 12.9 and females 12.8 mg/L). No person had plasma vitamin A deficiency (< 0.01 mg/L) and only 0.1% had vitamin E deficiency (< 5.0 mg/L). In contrast, plasma vitamin C was on the low side and higher in Chinese than Malays and Indians. Mean plasma vitamin C levels were: Chinese (males 6.3 and females 8.4 mg/L), Malays (males 5.1 and females 6.4 mg/L), and Indians (males 5.7 and females 6.9 mg/L). Likewise, the proportions with plasma vitamin C deficiency (< 2.0 mg/L) were lower in Chinese (males 14.4 and females 0.7%), than Malays (males 19.7 and females 7.2%), and Indians (males 17.8 and females 11.0%). Relatively low levels of plasma vitamin C may contribute to the high rates of coronary heart disease and cancer in Singapore. In particular, lower plasma vitamin C in Malays and Indians than Chinese may contribute to their higher rates of coronary heart disease. However, plasma vitamin C does not seem to be involved in the higher rates of cancer in Chinese than Malays and Indians. The findings suggest a relatively low intake of fresh fruits and a higher intake is recommended. Also, food sources of vitamin C may be destroyed by the high cooking temperatures of local cuisines, especially the Malay and Indian ones.

Adult↗

PubMed1981

Differences between proline and lysine hydroxylations in their inhibition by zinc or by ascorbate deficiency during collagen synthesis in various cell types.

The addition of Zn2+ inhibited lysine hydroxylation markedly less effectively than it did proline hydroxylation in chick embryo tendon cells, 3T6 fibroblasts and lysyl hydroxylase-deficient Ehlers-Danlos Syndrome Type VI fibroblasts. With low Zn2+ concentrations, a similar difference was also seen in chick embryo cartilage cells, whereas with high concentrations both hydroxylations were affected to the same extent in this cell type. Ascorbate deficiency likewise had a much less effect on lysine than proline hydroxylation when studied with 3T6 fibroblasts. As these two effectors involve quite different mechanisms, it is suggested that relative insensitivity to inhibition may be a property of lysine hydroxylation seen in many cell types with a number of agents. Studies on the mechanism of the difference in the inhibition indicates that the phenomenon is probably not due to differences in the kinetic constants of Zn2+ and ascorbate for the two enzymes. Neither is it probably to any major extent due to delayed procollagen triple helix formation nor a difference in the location of the two hydroxylases within the cisternae of the rough endoplasmic reticulum. The difference similarly cannot be explained solely by an excess of lysyl hydroxylase in the cell. It may thus be due either to some other intracellular property or to the combined effect of several factors.

Animals↗

PubMed2005

Possible interplay between vitamin C deficiency and prolactin in pregnant women with premature rupture of membranes: facts and hypothesis.

The precise etiologic mechanisms involved in the premature rupture of membranes (PROM) during pregnancy, the main cause of preterm delivery worldwide, are unknown. Previous studies have shown that: (a) the rupture of chorioamniotic membranes is related to an imbalance between synthesis and degradation of collagen induced by the overexpression/activity of various matrix metalloproteinases (MMP); (b) during human labor and delivery the expression of prolactin receptors (PRL-R) increases in chorioamniotic membranes, decidua and placenta; (c) prolactin (PRL) can influence the synthesis of prostaglandins, the expression of some MMP (MMP-2, MMP-9 and decysin) and tissue inhibitors of MMP in general; (d) vitamin C deficiency induces the expression/activity of extracellular MMP and is considered a risk factor for PROM; and (e) vitamin C potentiates the dopamine-mediated inhibition of PRL in rats. The present hypothesis proposes that a decreased hypothalamic dopaminergic tone-and thus an increased synthesis/release of pituitary PRL - is induced by vitamin C deficiency below a critical threshold (<18 microg/10(8) leukocytes) and that both factors, in turn, would cause upregulation of the expression/activity of several MMP. The increased PRL concentrations (acting like a Th1-type cytokine) along with the overexpression of other proinflammatory cytokines would induce a premature switch from a favorable Th2-type immune response to a noxious Th1-type immune response in the intrauterine environment. This change, in conjunction with the upregulation of MMP-2 and MMP-9, would cause a premature imbalance between synthesis/degradation of collagen in chorioamniotic membranes (an "anticipation" of the normal parturition cascade?), which favors extracellular matrix degradation, proposed as the most relevant event in the genesis of PROM. This hypothesis represents a new dimension in the study of the etiology of PROM.

Ascorbic Acid Deficiency↗

PubMed1995

Morphological and biochemical changes in lenses of guinea pigs after vitamin-C-deficient diet and UV-B radiation.

The effect of ultraviolet B (UV-B) radiation and a vitamin-C-deficient (VCD) diet on guinea pig lenses was investigated. The initial lens changes in the VCD group were observed by slit-lamp examination 6 weeks after the start of the VCD treatment; after 12 weeks the changes in the posterior subcapsular region became more prominent, and the dissociation around the posterior suture became wider and slightly deeper toward the posterior cortex. The high concentration of lens oxidized glutathione (GSSG), and the low ratio of reduced glutathione (GSH) to oxidized glutathione (GSH/GSSG) on the lens posterior region correlated with density changes in the corresponding layers as measured by Scheimpflug images with linear microdensitometry. It is suggested that the strong oxidative stress of the VCD diet caused the damage at the posterior part of the lens. UV-B radiation appeared to accelerate cataract progression in lenses that lack vitamin C.

Animals↗