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Results for “ASCORBIC ACID DEFICIENCY”

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PubMed1984

Collagen degradation in human lung fibroblasts: extent of degradation, role of lysosomal proteases, and evaluation of an alternate hypothesis.

Experiments were conducted to determine the extent and variability of collagen degradation in human fetal lung fibroblasts. Cells were incubated with [14C]proline, and degradation was measured by determining the hydroxy[14C]proline in a low molecular weight fraction relative to total hydroxy[14C]proline. Average (basal) degradation in stationary phase HFL-1 cells incubated for 8 h was 16 +/- 3%, and substantial alterations in the composition of the labeling medium, e.g., omitting serum and varying pH between 6.8 and 7.8, had no effect. Organic buffers slightly lowered degradation in a manner that was independent of pH. Collagen degradation in two other lung cell lines, Wl-38 and lMR-90, did not differ from the level in HFL-1. Degradation was significantly higher (23 +/- 5%) in HFL-1 cultures labeled for 24 h rather than 8 h, and pulse-washout experiments showed that the rate of degradation was not uniform: after an 8-h pulse, 11% of the hydroxy [14C]proline in the medium was in the low molecular weight fraction, but 31% was in this fraction after a 16-h washout. The lack of effect of either serum deprivation or elevated pH suggests that lysosomal proteases have no direct role in basal degradation; however, NH4Cl decreased the enhanced degradation observed in ascorbate deficiency to basal level, indicating that abnormal molecules synthesized under those conditions are degraded by lysosomal proteases. The appearance of small hydroxy[14C]proline-containing molecules was inhibited by alpha alpha'dipyridyl and cycloheximide in a dose-dependent and reversible manner, demonstrating that their production depends on enzymatic hydroxylation of proline and protein synthesis.

2,2'-Dipyridyl↗

PubMed2000

Fractured neck of femur in black patients: a prospective study.

We explored the role of iron overload, deficiency of vitamin C and alcohol abuse in the aetiology of cervical and intertrochanteric fractures of the neck of the femur as a result of minor trauma. We studied prospectively 72 patients (45 men, 27 women). Levels of serum iron markers, vitamin C and alcohol markers were measured. Consumption of alcohol was estimated using questionnaires. The findings were compared with those of an age- and gender-matched control group. The mean age of the men was 59.5 years and of the women 66.9 years, with a male predominance. In the men, iron overload, as shown by high levels of serum ferritin (p < 0.001) and deficiency of vitamin C (p < 0.03), as well as abuse of both Western and the traditional type of alcohol, appear to be important aetiological factors. In women, alcohol abuse was also common, but iron markers and levels of vitamin C did not differ significantly from the control group.

Black or African American↗

PubMed1999

Vitamin C deficiency in guinea pigs differentially affects the expression of type IV collagen, laminin, and elastin in blood vessels.

Vitamin C deficiency causes morphologic changes in the endothelial and smooth muscle compartments of guinea pig blood vessels. Endothelial cells synthesize the basement membrane components, type IV collagen and laminin, and smooth muscle cells synthesize elastin in blood vessels. Therefore, we examined the possibility that vitamin C deficiency affects the expression of these proteins. Decreased expression of types I and II collagens in other tissues of vitamin C-deficient guinea pigs is associated with weight loss and the consequent induction of insulin-like growth factor binding proteins; thus we also used food deprivation to induce weight loss. Female guinea pigs received a vitamin C-free diet, supplemented orally with ascorbate. Vitamin C-deficient guinea pigs received the same diet but no ascorbate, and the food-deprived group received no food, but were supplemented with vitamin C. Concentrations of mRNAs for basement membrane components and elastin in blood vessels were measured by Northern blotting; overall basement membrane metabolism was assessed by measuring immunoreactive laminin and type IV 7S collagen in serum. Laminin mRNA in blood vessels and serum laminin concentrations were unaffected by vitamin C deficiency. Concentrations of type IV collagen and elastin mRNAs in blood vessels were not significantly affected in moderately scorbutic guinea pigs (0-7% weight loss), but with increased weight loss, type IV collagen mRNA was 57% (P < 0.05) and elastin mRNA was 3% (P < 0. 01) of normal values. In food-deprived guinea pigs, type IV collagen mRNA was 51% (P < 0.05) and elastin mRNA was 35% (P < 0.05) of normal. Serum type IV 7S collagen concentrations were 25% of normal in scorbutic guinea pigs with extensive weight loss. The lower expression of type IV collagen and elastin mRNAs in blood vessels may contribute to defects observed in blood vessels during scurvy.

Amino Acid Sequence↗

PubMed1985

Cognitive effects of nutritional deficiency.

Deficiencies of various nutrients, primarily vitamins, impair cognition. The link is strongest for vitamin B12, thiamine, and niacin. Yet even for these, the role of mild "subclinical" or multiple deficiencies in the genesis of mental dysfunction is unclear. Most information in this field is based on animal studies often poorly applicable to the human condition or on clinical pathology complicated by advanced age, alcoholism, and intercurrent disease. There is a need for well controlled, double-blind, prospective trials to elucidate the cognitive effects of malnutrition.

Adult↗

PubMed2004

Vitamin C in health and disease.

Vitamins are essential to maintain normal metabolic processes and homeostasis within the body. The amount of a specific vitamin required by an individual varies considerably and it is influenced by such factors as body size, growth rate, physical activity, and pregnancy. Most vitamins are stored minimally in human cells, but some are stored in liver cells to a greater extent. Vitamins A and D, for example, may be stored in sufficient amounts to maintain an individual without any intake for 5 to 10 months and 2 to 4 months, respectively. However, a deficiency of vitamin B compounds (except vitamin B12) may be noted within days, and the lack of vitamin C will manifest within weeks and may result in death in 5 to 6 months. The current recommended dietary allowance (RDA) of vitamin C is 75 mg for woman and 90 mg for men, based on the vitamin's role as an antioxidant as well as protection from deficiency. High intakes of the vitamin are generally well tolerated, however, a Tolerable Upper Level (TUL) was recently set at 2 g based on gastrointestinal upset that sometimes accompanies excessive dosages. Several populations warrant special attention with respect to vitamin C requirements. These include patients with periodontal disease, smokers, pregnant and lactating women, and the elderly.

Alzheimer Disease↗

PubMed1977

Malnutrition in surgical patients. An unrecognised problem.

Indices of nutritional state were measured in 105 surgical patients. The indices were chosen to give information on protein-calorie malnutrition, anaemia, vitamin deficiency. Abnormal values for the various indices were common in the group as a whole and most frequent (50%) in patients who were still in hospital more than a week after major surgery. These patients had a high frequency of anaemia, vitamin deficiency, weight-loss, loss of arm-muscle bulk, and low plasma levels of transferrin and albumin. These abnormalities had gone almost entirely unrecognised, even in patients with sepsis after major surgery, who would benefit from improvement in nutritional state.

Adolescent↗

PubMed2006

Incidence of vitamin deficiency after laparoscopic Roux-en-Y gastric bypass in a university hospital setting.

Vitamin deficiency after gastric bypass surgery is a known complication. The purpose of this study was to measure the incidence of vitamin deficiency after laparoscopic Roux-en-Y gastric bypass in a university hospital setting. All patients who underwent laparoscopic Roux-en-Y gastric bypass from January 2002 to December 2004 and completed a 1- and 2-year follow-up after surgery were selected. Of the total 493 patients, 318 (65%) had vitamin results at 1-year follow-up. Of the 366 eligible for the 2-year follow-up, 141 (39%) had vitamin results. Patients were further grouped based on gender, race, and Roux limb length, and incidence of vitamin deficiencies were studied. The incidence of vitamin A (retinol) deficiency was 11 per cent, vitamin C was 34.6 per cent, vitamin D25OH was 7 per cent, vitamin B1 was 18.3 per cent, vitamin B2 was 13.6 per cent, vitamin B6 was 17.6 per cent, and vitamin B12 was 3.6 per cent 12 months after surgery. There was no statistical difference in the incidence of vitamin deficiencies between 1 and 2 years. In univariate and multivariate logistic regression of 1- and 2-year follow up, black patients (vitamins A, D, and B1 for 1 year and B1 and B6 for 2 years) and women (vitamin C at 1 year) were more likely to have vitamin deficiencies. Vitamin deficiencies after laparoscopic Roux-en-Y gastric bypass are more common and involve more vitamins, even those that are water soluble, than previously appreciated. Black patients tend to have more deficiencies than other groups. The bariatric surgeon should be committed to the long-term follow-up and care of these patients. Further prospective and randomized studies are necessary to provide appropriate guidelines for supplementation.

Adult↗

PubMed2002

Vitamin C, E and A levels in maternal and fetal blood for Czech and Gypsy ethnic groups in the Czech Republic.

Vitamin C, E and A levels in maternal and cord blood sera were examined at delivery in two districts of the Czech Republic. Information on personal and social characteristics, health, ethnicity, and lifestyle was also collected. A highly significant correlation between ascorbate levels in maternal and cord blood was found. Vitamin C levels in cord blood were about 1.7 times those in maternal blood. This ratio was much higher for mothers deficient in vitamin C: it was about 3 for deficient nonsmokers and as high as 5 for deficient mothers who smoked cigarettes (p < 0.01). This finding may suggest a compensatory mechanism in fetuses that are endangered by oxidative stress. The mean maternal blood levels of vitamin A and E were higher than in fetal blood (both p < 0.001). The mean fetal/maternal ratios were 0.7 for vitamin A and 0.2 for vitamin E levels; these ratios were considerably higher for mothers deficient in a particular vitamin as compared with those for well-nourished mothers. Ascorbate levels were associated with maternal education and smoking. Significantly decreased vitamin C levels were observed in Gypsy mothers and their babies; this may be attributed to unfavorable diet and smoking habits: about 78% of Gypsy mothers admitted smoking as compared with 31% of Czech mothers.

Alcohol Drinking↗

PubMed1976

Influence of ascorbic acid on selenium nutrition in the chick.

Experiments were conducted to determine the nature of the effect of dietary ascorbic acid on selenium nutrition in the chick. Results showed that ascorbic acid resulted in increased activities of the selenium-containing enzyme glutathione peroxidase in plasma, accompanied by an apparent reduction in the dietary selenium requirement of the vitamin E-deficient chick. The ascorbic acid contents of plasma, liver, kidney and adrenals were not affected by selenium or vitamin E deficiencies, indicating that selenium-vitamin E deficient chicks are not rendered scrobutic. Absorption experiments using ligated duodenal loops or oral doses indicated that dietary ascorbic acid promoted the enteric absorption of selenium but did not affect the absorption of vitamin E. These results support the hypothesis previously reported that factors which inhibit the oxidation of dietary selenium promote its absorption and, perhaps, its post-absorptive utilization in metabolically active components of the cell.

Animals↗

PubMed1992

[Scurvy. A study of 13 cases].

Scurvy or vitamin C deficiency disease it is seen nowadays with a very low frequency. Thirteen cases in which scurvy was diagnosed at Hospital del Niño "Rodolfo Nieto Padrón" at Villahermosa, Tabasco, Mexico, in a 5 years period (from March 1985 through May 1990) were reviewed. The cases occurred in infants between 5 and 18 months. All of them had a third grade malnutrition and also had a concomitant infectious disease. Pain localized on extremities was the most important symptom. Anemia was seen in all cases. Roentgenologic studies showed the presence of Fraenkel line, scurvy lattice and subperiostitic calcifications in all cases; these changes are characteristic of scurvy. The chief complaint, physical findings, radiologic signs and the response to treatment with ascorbic acid will give the clue to make diagnosis. The present report shows the incidence of scurvy in the southeast of the Mexican Republic. We are aware about this disease as a great health problem even nowadays which needs the responsibility of all those who care for infants to assist educational aspects mainly in urban areas.

Anemia, Hypochromic↗

PubMedDate not supplied

Effects of vitamin C deficiency on physiology of male reproductive organs of guinea pigs.

Vitamin C dietary deficiency in guinea pigs markedly affected the androgen-sensitive parameters of the reproductive tissues--testis, epididymis, vas deferens, and accessory sex glands--and caused an "androgen-deprived effect" in these target organs. This in turn altered their internal milieu and caused changes in their metal ion profile and the morphology, motility, and density of spermatozoa in the cauda epididymis and vas deferens. The sensitivity of the vas deferens to adrenaline was also reduced in scorbutic guinea pigs, thus decreasing their fertility rate. The primary action seems to be at the level of the testis, and androgen deprivation and partial antifertility effects are probably secondary manifestations consequent to the primary effect. The present study demonstrated that ascorbic acid is essential for maintaining the physiological integrity of the androgen target reproductive organs in guinea pigs.

Animals↗

PubMed1975

Tissue changes induced by marginal vitamin C deficiency.

Chronic marginal vitamin C deficiency in guinea pigs results in alterations in certain tissues that are quite different from those observed following acute deficiency. In autonomic ganglia, although changes observed in the organelles of some cells are similar to those seen in acute deficiency, the specific changes are the presence of large numbers of cilia in the cytoplasm of both ganglion cells and their associated neuroglia and the marked proliferation of collagen fibers in the extracellular spaces. The evidence presented points to a link between vitamin C and arteriosclerosis. One mode of interaction may be the effect of latent vitamin C deficiency on cholesterol metabolism. The data presented indicate important changes in the liver with marked increases of agranular endoplasmic reticulum. Together with the liver cholesterol studies, the indications suggest an increased cholesterol deposition in the liver. Light-microscopic sections of the aorta reveal alterations in many of these vessels ranging from endothelial proliferation to large, well-formed musculofibrotic arteriosclerotic plaques.

Animals↗

PubMed1978

[Comparative histological studies of mouth mucosa, gingiva and desmodont in normal guinea pigs and guinea pigs fed a vitamin C deficient diet].

The changes occurring in the oral mucosa, gingivae and periodontium of guinea pigs fed a vitamin C-deficient diet were determined by means of histological comparison with animals on a normal diet. The following results were obtained from the scorbutic guinea pigs: --detachment of the horny layer from the underlying epithelium, --bullous cells in the spinose and the granular layer, --formation of periodontal pockets, --reduction in number and disorientation of collagenous fibres of the periodontium associated with loosening of the molars.

Animals↗

PubMed1990

Has lack of vitamin C any role in the aetiology of tropical pyomyositis?

The plasma concentration of vitamin C of 14 patients with tropical pyomyositis without clinical evidence of scurvy and that of II age and sex-matched controls was determined in order to ascertain whether or not there was a deficiency of the vitamin in this condition. The results show that the mean plasma concentrations of vitamin C of patients were slightly higher (15.9 +/- 6.4 g/l) than those of controls (12.0 +/- 4.5 g/l). The differences, however, were not statistically significant (P greater than 0.25). It is therefore concluded that lack of vitamin C does not play a part in the aetiology of tropical pyomyositis.

Ascorbic Acid↗

PubMed1997

Use of a new vitamin C-deficient diet in a depletion/repletion clinical trial.

To conduct an inpatient study on the recommended dietary allowance (RDA) for vitamin C, we developed a unique vitamin C-deficient diet using a nutrient database and selective menus. Fourteen different menus were developed offering > 300 items with 0-2.4 mg vitamin C per serving. During the 4-6 mo volunteers were hospitalized, daily dietary vitamin C was restricted to < or = 5.0 mg. The mean daily dietary vitamin C intake was < 3.9 mg for the seven study subjects. With concurrent supplementation, the diet provided > or = 85% of the RDA for 17 essential nutrients. Within 3 wk of admission the diet induced vitamin C deficiency as indicated by plasma concentrations, which decreased from 23 +/- 6.9 to 6.9 +/- 2.0 mumol/L. Daily intake of vitamin C and five other nutrients was determined by nutrient database analyses. Mean energy, protein, the iron were 105-185% of the RDA and total and saturated fat were 32% and 10% of energy, respectively. Weight and nutritionally relevant indexes remained normal. Dietary adherence, calculated by the number of days with < or = 5.0 mg vitamin C per total study days, was 88-98% per repletion dose. Computer analyses of menu selections permitted individual preferences to be met while restricting vitamin C intake to < or = 5.0 mg/d. There were no complications from the diet during the depletion and repletion phase. With this diet, ascorbic acid pharmacokinetics for escalating doses could be determined in healthy volunteers.

Ascorbic Acid↗

PubMed1997

Micronutrients and immune function: some recent developments.

Micronutrient deficiencies probably have few direct effects on the functioning of immune cells. The main effect appears to be a reduction in cell mass that may indirectly affect immune cell function, particularly where T helper cell numbers are reduced. Results of many human studies are contradictory. Some of this contradiction may be accounted for by the fact that disease may lower concentrations of micronutrients in plasma that may be misinterpreted as deficiency. Low plasma vitamin A concentrations however appear to impair immune responsiveness and have deleterious effects on membrane integrity and mucosal function. Zinc may have similar effects on gut integrity and appears to be particularly useful in the treatment of acute diarrhoea. Low concentrations of other nutrients such as ascorbate and iron, may not necessarily impair immune function. Low plasma ascorbate may assist the removal of iron from plasma and low iron concentrations appear to increase the cytotoxicity of macrophages.

Acute-Phase Reaction↗

PubMed1993

[Vitamin C deficiency: a rare cause of poorly tolerated severe anemia].

We report the case of a 82-year-old man, living in institution, hospitalized for a severe anaemia due to scurvy. Scurvy is rare in Occident. A multifactorial anaemia is usually associated with scurvy, but is rarely symptomatic. Alcoholism favours scurvy and anaemia. Treatment consisted of parenteral vitamin C supplementation associated with blood transfusion.

Aged↗

PubMedDate not supplied

[History of scurvy therapy and the injustice done to Dr. Maksim Nikolić-Miskovićev of Sremski Karlovci in the 19th century].

This paper reviews historical aspects regarding medical knowledge on scurvy, vitamin C deficiency, and its etiological factors. This disease used to affect naval-crews on long lasting sea voyages, soldiers during times of war and the poor. Although efficient therapy of scurvy (fresh vegetables, lemon juice) was known in the mid-18th century, its etiology was not known. It was believed to be caused by the cold, moist winds, unhealthy evaporations, malnutrition and it was called "alkaline disease". It was established that acid substances like lemon juice, had beneficial effects on the disease. However, it was soon generally accepted that it was caused by deficient diet. In 1830, Dr. John Elliotson, Professor of Medicine at London University supported this opinion. In 1928, Albert Szent Gyordyi, professor of Chemistry and Biochemistry at Szeged and Budapest Universities, isolated vitamin C from green pepper, vegetable proved to be rich with vitamin C. Due to this discovery, and some discoveries regarding biological processes, he was awarded the Nobel Prize for medicine and physiology in 1937. Back in 1864, a military doctor in Belgrade, Dr. Maksim Nikolić-Miskovićev from Sremski Karlovci, wrote to Ministry of Defence of the Serbian Principality. He informed the authorities about a successful, quick and cheap cure for scurvy-pepper juice. A medical board headed by Dr. Vladan Dordević was formed to evaluate his discovery. Dr. Nikolić-Miskovićev was underestimated and laughed at, and his discovery was completely forgotten. The aim of this paper was to correct injustice done to Dr. Maksim Nikolić-Miskovićev.

Ascorbic Acid↗